Abstract: A terahertz oscillator may include a first insulating layer, an electron emitter on the first insulating layer, adapted to emit an electron beam, and including a cathode, an anode, an oscillating circuit, and a collector sequentially disposed, spaced apart from each other, on the first insulating layer in a direction in which the electron beam is emitted from the electron emitter, wherein the oscillating circuit converts energy of the electron beam to energy of an electromagnetic wave, and wherein the collector collects the electron beam, an output unit adapted to emit the electromagnetic wave from the oscillating circuit to outside of the terahertz oscillator, and an electron emitting material layer. The cathode may include a first curved portion that extends in a direction perpendicular to the first insulating layer. The electron emitting material layer may be on an inner surface of the first curved portion of the cathode.

Abstract: A system for distributing a reference oscillator signal includes a clock having a reference oscillator and a femtosecond laser stabilized by the reference oscillator. The system also includes at least one beamsplitter configured to split the femtosecond laser. The system further includes one or more remote nodes that are spaced from the clock. The remote nodes are configured to generate reference signals based on the split femtosecond laser.

Abstract: A system for synchronizing a first clock and a second clock includes a receiver associated with the first clock, configured to receive a remote pulse from the second clock. The remote pulse has a pulse repetition frequency and spectral characteristics that are known to the local clock. The system also includes a local pulse emitter configured to create a local pulse at the first clock, and optics configured to align the local pulse and the remote pulse. The system further includes an interferometer configured to create an interference pattern between the local pulse and the remote pulse. A controller is provided that is configured to calculate a time delay between the first clock and the second clock based on the interference pattern between the local pulse and the remote pulse.

Abstract: A spin torque oscillator and a method of making same. The spin torque oscillator is configured to generate microwave electrical oscillations without the use of a magnetic field external thereto, the spin torque oscillator having one of a plurality of input nanopillars and a nanopillar having a plurality of free FM layers.

Abstract: A spin transfer oscillator (STO) device is disclosed with a giant magnetoresistive (GMR) junction comprising a magnetic resistance layer (MRL)/spacer/magnetic oscillation layer (MOL) configuration, and a MR sensor including a sensing layer/junction layer/reference layer configuration. MOL and sensing layer are magnetostatically coupled and separated by a conductive spacer. MRL has perpendicular magnetic anisotropy while MOL and sensing layer have a Mst (saturation magnetization×thickness) value within ±50% of each other. When a magnetic field is applied perpendicular to the planes of the MOL and a high density current flows from the conductive spacer to the MRL, a MOL oscillation state with a certain frequency is induced. Consequently, the sensing layer oscillates with a similar RF frequency and when a low density current flows across the MR sensor, an AC voltage signal is generated to determine the sensing layer frequency that can be varied by adjusting the applied field.

Abstract: According to one embodiment, there is provided a spin torque oscillator including an oscillation layer formed of a magnetic material, a spin injection layer formed of a magnetic material and configured to inject a spin into the oscillation layer, and a current confinement layer including an insulating portion formed of an oxide or a nitride and a conductive portion formed of a nonmagnetic metal and penetrating the insulating portion in a direction of stacking. The conductive portion of the current confinement layer is positioned near a central portion of a plane of a device region including the oscillation layer and the spin injection layer.

Abstract: A spin transfer oscillator (STO) device is disclosed with a giant magnetoresistive (GMR) junction comprising a magnetic resistance layer (MRL)/spacer/magnetic oscillation layer (MOL) configuration, and a MR sensor including a sensing layer/junction layer/reference layer configuration. MOL and sensing layer are magnetostatically coupled and separated by a conductive spacer. MRL has perpendicular magnetic anisotropy while MOL and sensing layer have a Mst (saturation magnetization×thickness) value within ±50% of each other. When a magnetic field is applied perpendicular to the planes of the MOL and a high density current flows from the conductive spacer to the MRL, a MOL oscillation state with a certain frequency is induced. Consequently, the sensing layer oscillates with a similar RF frequency and when a low density current flows across the MR sensor, an AC voltage signal is generated to determine the sensing layer frequency that can be varied by adjusting the applied field.

Abstract: A spin transfer oscillator (STO) structure is disclosed that includes two assist layers with perpendicular magnetic anisotropy (PMA) to enable a field generation layer (FGL) to achieve an oscillation state at lower current density for MAMR applications. In one embodiment, the STO is formed between a main pole and write shield and the FGL has a synthetic anti-ferromagnetic structure. The STO configuration may be represented by seed layer/spin injection layer (SIL)/spacer/PMA layer 1/FGL/spacer/PMA layer 2/capping layer. The spacer may be Cu for giant magnetoresistive (GMR) devices or a metal oxide for tunneling magnetoresistive (TMR) devices. Alternatively, the FGL is a single ferromagnetic layer and the second PMA assist layer has a synthetic structure including two PMA layers with magnetic moment in opposite directions in a seed layer/SIL/spacer/PMA assist 1/FGL/spacer/PMA assist 2/capping layer configuration. SIL and PMA assist layers are laminates of (CoFe/Ni)x or the like.

Abstract: An atomic clock comprises helium 3 plasma as measurement medium, which is taken to the plasma state to exploit the metastable state of the material and the levels of the hyperfine structure, the lifetime of which is long and which thus enable an easier measurement than the excitations of gaseous atoms.

Abstract: An atomic clock including a mechanism applying both a static magnetic field and two oscillating magnetic fields, all mutually perpendicular, in a magnetic shield. The amplitudes and frequencies of the oscillating magnetic fields may be chosen so as to annihilate energy variations between sub-transition levels of excited atoms and to reinforce a clock output signal, and with low sensitivity to defects in regulation.

Abstract: An atomic clock at optical frequency based on atomic beam and a method for generating the atomic clock comprises: The atomic beam (8) is ejected from a pile mouth after heating an atomic pile (1) in a vacuum chamber (2); A laser (4) corresponding to frequency of a clock transition transfers the atomic beam (8) from a ground state of the clock transition to an excited state of the clock transition in a adiabatic passing mode; After interaction with the laser corresponding to the frequency of a clock transition, the atomic beam (8) passes a signal detection region with a detection laser (5), and after the interaction with the detection laser (5), each of the atoms gives off a photon of spontaneous emission; An emitted fluorescence photon signal from atoms which is excited by the detection laser (5) is explored; A clock laser (4) for exploring transition frequency of an atomic clock is modulated.

Abstract: An atomic oscillator includes: a gas cell in which a gaseous metal atom is sealed; heating units heating the gas cell to a predetermined temperature and being a first heater and a second heater; a light source of exciting light exciting the metal atom in the gas cell; a light detecting unit detecting the exciting light which has passed through the gas cell; a substrate including at least a temperature controlling circuit for the heating units; a first heater wiring coupling the first heater and the substrate; a second heater wiring coupling the second heater and the substrate; and a third heater wiring coupling the first heater and the second heater.

Abstract: Oscillators and method of operating the same are provided, the oscillators include a magnetic layer, and a magnetization fixing element configured to fix a magnetization direction of the magnetic layer. The oscillators generate a signal by using precession of a magnetic moment of the magnetic layer.

Abstract: Techniques involving the generation of signals at particular frequencies are disclosed. For instance, an apparatus may include an oscillator module, a synthesizer module, and a control module. The oscillator module produces an oscillator signal having a first frequency. From the oscillator signal, the synthesizer module produces an output signal having a second frequency. A frequency multiplier corresponds to the first and second frequencies. The control module selects the first frequency and the frequency multiplier such that a difference between the second frequency and a nearest integer multiple of the first frequency is greater than a predetermined threshold. As a result, reductions in spurious outputs may be achieved.

Abstract: A method includes causing a common-resonator mode resonating with a transition between |2>i and |3>i that are coupled to each other by a transition having a homogenous broadening ?Ehomo greater than an energy difference between |0>i and |1>i, an energy difference between |2>i and |3>i being greater than ?Ehomo, transferring states of m quantum bits represented by |0>k and |1>k to |4>k and |5>k, respectively, when a quantum-bit-gate operation using the common-resonator mode is executed between the quantum bits represented by m physical systems k, |E(|u>k)?E(|v>k)|>?Ehomo, u, v?{2, 3, 4, 5}, u?v, executing adiabatic passage between the physical systems k, using light that resonates with a transition between |3>k and |4>k and a transition between |3>k and |5>k, executing the quantum-bit-gate operation between the quantum bits, and transferring, to |0>k and |1>k, the states represented by |4>k and |5>k, respectively.

Abstract: An optical module of an atomic oscillator using a quantum interference effect includes a light source to generate first light including a fundamental wave having a center wavelength, and including a first sideband wave and a second sideband wave having wavelengths that are different from each other, a wavelength selection unit that emits second light by selecting the first sideband wave and the second sideband wave of the first light and by allowing them to pass through, a gas cell in which an alkali metal gas is sealed and to which the second light is irradiated, and a light detection unit that detects an intensity of the second light passing through the gas cell.

Abstract: This radio-frequency oscillator includes a magnetoresistive device in which an electric current is able to flow. The magnetoresistive device includes a first magnetic layer, known as a “trapped layer”, whereof the magnetization is of fixed direction. The magnetoresistive device further includes a second magnetic layer known as a “free layer” and a non-magnetic layer, known as an “intermediate layer”, interposed between the first and second layer, known as the intermediate layer. The oscillator further includes means capable of causing an electron current to flow in said layers constituting the aforementioned stack and in a direction perpendicular to the plane which contains said layers. One of the three layers constituting the magnetoresistive device includes at least one constriction zone of the electric current passing through it.

Abstract: An atomic oscillator includes a cell containing a mixture gas of alkali metal atoms and isotopes of the alkali metal atoms, a light source that has coherency and irradiates the gas with lights including a first resonant light pair having two different frequency components for one center frequency and a second resonant light pair, a photo detector that generates a detection signal corresponding to intensity of light passing through the gas, and a frequency control part that controls, based on the detection signal, frequencies of the first resonant light pair to cause an electromagnetically induced transparency phenomenon to occur in the alkali metal atom and controls frequencies of the second resonant light pair to cause the electromagnetically induced transparency phenomenon to occur in the isotope of the alkali metal atom.

Abstract: An atomic oscillator includes: a gas cell in which a gaseous metal atom is sealed; heating units heating the gas cell to a predetermined temperature and being a first heater and a second heater; a light source of exciting light exciting the metal atom in the gas cell; a light detecting unit detecting the exciting light which has passed through the gas cell; a substrate including at least a temperature controlling circuit for the heating units; a first heater wiring coupling the first heater and the substrate; a second heater wiring coupling the second heater and the substrate; and a third heater wiring coupling the first heater and the second heater. In the atomic oscillator, the gas cell includes a cylindrical portion; and windows which respectively seal openings at both ends of the cylindrical portion and constitute an incident surface and an emitting surface on an optical path of the exciting light.

Abstract: A chip-scale atomic clock comprises a physics package and a laser die located in a first thermal zone of the physics package. A quarter wave plate is mounted in the physics package and is in optical communication with the laser die. A vapor cell is mounted in the physics package and is in optical communication with the quarter wave plate. The vapor cell is located in a second thermal zone that is independent from the first thermal zone. An optical detector is mounted in the physics package and is in optical communication with the vapor cell. The first thermal zone provides a first operation temperature at a first stability point associated with the laser die, and the second thermal zone provides a second operation temperature at a second stability point associated with the vapor cell.

Abstract: The invention relates to a method of operating a spin-transfer torque structure to generate voltage oscillations, said structure comprising a first layer of magnetic material having a fixed magnetization vector, a spacer of non magnetic material and a second layer of magnetic material having a free magnetization vector. The method includes the application of a current (jop) through said structure and a magnetic field (Hext) in the plane of the second layer. It makes use of a region of bistability and hysteretic behaviour to trigger and stop the voltage oscillations.

Abstract: An apparatus including a spin torque oscillator configured to receive an input electric current and to produce a radio frequency output signal; and a tunable current source for providing an input electric current to the spin torque oscillator.

Abstract: An atomic ion clock with a first ion trap and a second ion trap, where the second ion trap is of higher order than the first ion trap. In one embodiment, ions may be shuttled back and forth from one ion trap to the other by application of voltage ramps to the electrodes in the ion traps, where microwave interrogation takes place when the ions are in the second ion trap, and fluorescence is induced and measured when the ions are in the first ion trap. In one embodiment, the RF voltages applied to the second ion trap to contain the ions are at a higher frequency than that applied to the first ion trap. Other embodiments are described and claimed.

Abstract: A physical section of an atomic oscillator includes: a gas cell in which gaseous metal atoms are sealed, and the gas cell includes a first window having optical transparency; a light source that emits excitation light toward the metal atoms through the first window; a first heating unit that disposes at the first window and that is located between the first window and the light source; and a Peltier element that is stacked on the first heating unit, that is located between the first heating unit and the light source, and that decreases a temperature of a side of the Peltier element facing the light source than a temperature of an opposite side of the Peltier element facing the gas cell.

Abstract: Local magnetic field strength in a trapped ion atomic clock is measured in real time, with high accuracy and without degrading clock performance, and the measurement is used to compensate for ambient magnetic field perturbations. First and second isotopes of an element are co-located within the linear ion trap. The first isotope has a resonant microwave transition between two hyperfine energy states, and the second isotope has a resonant Zeeman transition. Optical sources emit ultraviolet light that optically pump both isotopes. A microwave radiation source simultaneously emits microwave fields resonant with the first isotope's clock transition and the second isotope's Zeeman transition, and an optical detector measures the fluorescence from optically pumping both isotopes.

Abstract: In one embodiment, a VCSEL includes a plurality of semiconductor layers, an insulative region, a resistive region, and a remainder region. The semiconductor layers include a lower mirror, an active region, and an upper mirror. The active region is disposed over the lower mirror and includes a first lasing region. The upper mirror is disposed over the active region. The insulative region and the resistive region are integrally formed in the semiconductor layers. The remainder region includes the semiconductor layers except for the insulative region and the resistive region integrally formed in the semiconductor layers. The insulative region is disposed between the resistive region and the remainder region.

Abstract: An atomic oscillator, attention is paid to the fact that the degree of change of the energy difference between the two ground levels of the alkali metal atom with respect to the change of the magnetic field intensity is specific to each of the magnetic quantum numbers, a resonant light pair to cause a transition between the two ground levels corresponding to each of the plural magnetic quantum numbers is sequentially generated, plural pieces of profile information capable of specifying the energy difference between the two ground levels corresponding to each of the magnetic quantum numbers are sequentially acquired based on the detection signal, the change amount of the magnetic field intensity is specified based on the acquired plural pieces of profile information, and the control is performed so that the intensity of the magnetic field becomes constant.

Abstract: A polarization gain medium such as an emitting laser diode provides the optical pumping. An atomic vapor cell is positioned in the laser cavity providing spontaneous push-pull optical pumping inside the laser cavity. This causes the laser beam to be modulated at hyperfine-resonance frequency. A clock signal is obtained from electrical modulation across the laser diode.

Abstract: A physical section of an atomic oscillator includes at least: a gas cell including a cylindrical portion and first and second windows respectively hermetically-closing openings of both sides of the cylindrical portion to form a cavity in which gaseous metal atoms are sealed; a light reflection unit disposed on the first window; a first heating unit disposed to be closely attached to the second window and heating the gas cell at a predetermined temperature; a light source disposed so as to allow a light emitting part thereof to face the light reflecting unit, emitting excitation light exciting the metal atoms in the gas cell, and provided on a side, which is a reverse side to a side to which the gas cell is provided, of the first heating unit; a light detection unit detecting the excitation light reflected by the light reflection unit and provided also on a side, which is a reverse side to a side to which the gas cell is provided, of the first heating unit; and a Peltier element interposed between the light so

Abstract: A terahertz oscillator may include a first insulating layer, an electron emitter on the first insulating layer, adapted to emit an electron beam, and including a cathode, an anode, an oscillating circuit, and a collector sequentially disposed, spaced apart from each other, on the first insulating layer in a direction in which the electron beam is emitted from the electron emitter, wherein the oscillating circuit converts energy of the electron beam to energy of an electromagnetic wave, and wherein the collector collects the electron beam, an output unit adapted to emit the electromagnetic wave from the oscillating circuit to outside of the terahertz oscillator, and an electron emitting material layer. The cathode may include a first curved portion that extends in a direction perpendicular to the first insulating layer. The electron emitting material layer may be on an inner surface of the first curved portion of the cathode.

Abstract: A method to construct a chip-scale atomic clock is provided. The method comprises providing a scaffolding for components in a chip-scale atomic clock. The components include a laser and at least one other component. The method also includes operationally positioning the components on the scaffolding so that an emitting surface of the laser is non-parallel to partially reflective surfaces of the at least one other component.

Abstract: A chip-scale atomic clock comprises a physics package and a laser die located in a first thermal zone of the physics package. A quarter wave plate is mounted in the physics package and is in optical communication with the laser die. A vapor cell is mounted in the physics package and is in optical communication with the quarter wave plate. The vapor cell is located in a second thermal zone that is independent from the first thermal zone. An optical detector is mounted in the physics package and is in optical communication with the vapor cell. The first thermal zone provides a first operation temperature at a first stability point associated with the laser die, and the second thermal zone provides a second operation temperature at a second stability point associated with the vapor cell.

Abstract: Apparatus and methods for alkali vapor cells are provided. In one embodiment, a vapor cell for a Chip-Scale Atomic Clocks (CSAC) comprises a silicon wafer having defined within a first chamber, a second chamber, and a pathway connecting the first chamber to the second chamber; a first glass wafer anodically-bonded to a first surface of the silicon wafer; a second glass wafer anodically-bonded to an opposing second surface of the silicon wafer, wherein the first chamber defines an optical path through the vapor cell; and an alkali metal material deposited into the second chamber. The pathway connecting the first chamber to the second chamber is configured with a geometry that is at least partially inhibitive to alkali metal vapor flow.

Abstract: Designs and processes for thermally stabilizing a vertical cavity surface emitting laser (vcsel) in a chip-scale atomic clock are provided. In one embodiment, a Chip-Scale Atomic Clock includes: a vertical cavity surface emitting laser (vcsel); a heater block coupled to a base of the vcsel; a photo detector; a vapor cell, wherein the vapor cell includes a chamber that defines at least part of an optical path for laser light between the vcsel and the photo detector; and an iso-thermal cage surrounding the vcsel on all sides, the iso-thermal cage coupled to the heater block via a thermally conductive path.

Abstract: An atomic oscillator using an electromagnetically induced transparency phenomenon caused by irradiating a resonant light pair to an alkali metal atom, includes: a gaseous alkali metal atom; a light source that generates a plurality of lights having coherency and including a first light and a second light different from each other in frequency, and irradiates them to the alkali metal atom; a light detection part that receives a plurality of lights passing through the alkali metal atom and generates a detection signal including a beat signal of a specified frequency obtained by interference of the plurality of lights; and a frequency control part that performs frequency control of at least one of the first light and the second light based on the beat signal of the specified frequency included in the detection signal, and causes the first light and the second light to become a resonant light pair by which the electromagnetically induced transparency phenomenon is caused in the alkali metal atom.

Abstract: An apparatus in one example comprises a die structure that comprises a middle layer, a first outside layer, and a second outside layer. The middle layer comprises a cavity that holds an alkali metal, and one of the first outside layer and the second outside layer comprises a channel that leads to the cavity. The middle layer, the first outside layer, and the second outside layer comprise dies from one or more wafer substrates.

Abstract: A physic package for an atomic clock comprising: a block made of optical glass, a glass ceramic material or another suitable material that includes a plurality of faces on its exterior and a plurality of angled borings that serve as a vacuum chamber cavity, light paths and measurement bores; mirrors fixedly attached using a vacuum tight seal to the exterior of the block at certain locations where two light paths intersect; optically clear windows fixedly attached using a vacuum tight seal to the block's exterior over openings of the measurement bores and at one location where two light paths intersect; and fill tubes fixedly attached using a vacuum tight seal to the exterior of the block over the ends of the vacuum chamber cavity. This physics package design makes possible atomic clocks having reduced size and power consumption and capable of maintaining an ultra-high vacuum without active pumping.

Abstract: One embodiment of the invention includes an atomic clock system including an alkali beam cell and an interrogation system configured to generate an optical pump beam and at least one optical probe beam that illuminate a detection chamber of the beam cell to pump evaporated alkali metal atoms. An optical detection system can provide a microwave signal to the detection chamber and can measure an intensity of the optical pump beam to determine a transition frequency corresponding to optimum photon absorption of the evaporated alkali metal atoms. A photodetection system can measure an intensity of the at least one optical probe beam and to generate an intensity signal that is provided to the optical detection system to substantially cancel Doppler broadening of the transition frequency resulting from non-orthogonal planar movement of the evaporated alkali metal atoms relative to the optical pump beam and the at least one optical probe beam.

Abstract: An atomic oscillator that controls an oscillation frequency by using an optical absorption property derived from a quantum interference effect occurring when two kinds of resonance light are made incident as coherent light having different wavelengths from each other, includes an optical system that includes: a gas cell sealing metal atoms in a gas state therein; a coherent light source for supplying the resonance light to the metal atoms being in the gas cell; and a light detector for detecting light transmitted through the gas cell. In the atomic oscillator, a first refraction unit is formed at a light incident side, on which coherent light is made incident, of the gas cell.

Abstract: An atomic oscillator includes: a light-receiving element including a light-receiving section; a cell layer that is laminated on the light-receiving element and includes a cavity having an opening above the light-receiving section; gaseous alkali metal atoms sealed in the cavity; a transparent member to close the opening; and a light-emitting element to emit resonance light to the light-receiving section through the transparent member and the alkali metal atoms.

Abstract: An atomic clock having a physics package that includes a vacuum chamber cavity that holds atoms of Rb-87 under high vacuum conditions, an optical bench having a single laser light source, a local oscillator, a plurality of magnetic field coils, an antenna, at least one photo-detector and integrated control electronics. The single laser light source has a fold-retro-reflected design to create three retro-reflected optical beams that cross at 90° angles relative to one another in the vacuum chamber cavity. This design allows the single laser light source to make the required six trapping beams needed to trap and cool the atoms of Rb-87. The foregoing design makes possible atomic clocks having reduced size and power consumption and capable of maintaining an ultra-high vacuum without active pumping.

Abstract: An atomic oscillator using an electromagnetically induced transparency phenomenon caused by irradiation of a resonant light pair to an alkali metal atom, includes: a light source that generates a first light having a center frequency f1 and a plurality of frequency components different from each other in frequency by ?f, and a second light having a center frequency f2 and a plurality of frequency components different from each other in frequency by ?f; a light detection unit that detects intensities of lights including the first light and the second light passing through the alkali metal atom; and a control unit that controls, based on a detection result of the light detection unit, to cause a frequency difference between a specified frequency component of the first light and a specified frequency component of the second light to be equal to a frequency corresponding to an energy difference between two ground levels of the alkali metal atom, wherein a frequency difference between the center frequency f1 of th

Abstract: An atomic frequency acquisition apparatus includes: a cell enclosing atomic gas therein; a laser light source that oscillates a laser light that enters the cell and excites the atomic gas; and a photodetecting section that detects the laser light that has passed through the cell, wherein the cell has at least a laser light reflection section inside thereof.

Abstract: An optical system of an atomic oscillator that regulates an oscillation frequency by using an optical absorption property by one of a double resonance method utilizing light and micro waves and a coherent population trapping (CPT) method utilizing a quantum interference effect produced by two kinds of resonance light, includes: a light source emitting the resonance light; a gas cell disposed at an emitting side of the light source, sealing a gaseous metal atom therein and transmitting the resonance light through a metal atom gas; a light detecting unit detecting the transmitted light that is transmitted through the metal atom gas; and a fluorescence blocking unit blocking at least a part of fluorescence, which is emitted from the metal atom gas to the light detecting unit, and disposed between the metal atom gas and the light detecting unit.

Abstract: A quantum interference device for causing an electromagnetically induced transparency phenomenon to occur in an alkali metal atom by a resonant light pair including a first resonant light and a second resonant light, includes: a light source to generate a plurality of the first resonant lights different from each other in frequency by ?? and a plurality of the second resonant lights different from each other in frequency by ??; a magnetic field generation unit that applies a magnetic field to the alkali metal atom; a light detection unit that detects intensities of lights including the first resonant lights and the second resonant lights passing through the alkali metal atom; and a control unit that controls to cause a frequency difference between the specified first resonant light and the specified second resonant light to become equal to a frequency difference corresponding to an energy difference between two ground levels of the alkali metal atom based on a detection result of the light detection unit, whe

Abstract: The present invention provides a system and method for achieving a calibration-free primary atomic clock standard operating at the 0-0 transition free-atom frequency, thus creating a primary frequency standard, with attributes that include scalable to chip-scale dimensions and power consumption.

Abstract: One embodiment of the invention includes an alkali beam cell system that comprises a reversible alkali beam cell. The reversible alkali beam cell includes a first chamber configured as a reservoir chamber that is configured to evaporate an alkali metal during a first time period and as a detection chamber that is configured to collect the evaporated alkali metal during a second time period. The reversible alkali beam cell also includes a second chamber configured as the detection chamber during the first time period and as the reservoir chamber during the second time period. The reversible alkali beam cell further includes an aperture interconnecting the first and second chambers and through which the alkali metal is allowed to diffuse.

Abstract: One embodiment of the invention includes an atomic clock system including an alkali beam cell and an interrogation system configured to generate an optical pump beam and at least one optical probe beam that illuminate a detection chamber of the beam cell to pump evaporated alkali metal atoms. An optical detection system can provide a microwave signal to the detection chamber and can measure an intensity of the optical pump beam to determine a transition frequency corresponding to optimum photon absorption of the evaporated alkali metal atoms. A photodetection system can measure an intensity of the at least one optical probe beam and to generate an intensity signal that is provided to the optical detection system to substantially cancel Doppler broadening of the transition frequency resulting from non-orthogonal planar movement of the evaporated alkali metal atoms relative to the optical pump beam and the at least one optical probe beam.

Abstract: The present invention is related to a device and corresponding methods for generating an oscillating signal. The device comprises a means for providing a current of spin polarised charge carriers, a magnetic, e.g. ferromagnetic, excitable layer adapted for receiving the generated current of spin polarised charge carriers thus generating an oscillating signal with a frequency Vosc and an integrated means for interacting with said magnetic, e.g. ferromagnetic, excitable layer such that a selection of said oscillation frequency is achieved. No external field needs to be applied to select or tune the frequency. Different types of integrated means can be used, such as e.g. means inducing mechanical stress in the magnetic, e.g. ferromagnetic, excitable layer, means inducing exchange bias interactions and means inducing magnetostatic interactions.

Abstract: A microfabricated ion frequency standard (i.e. an ion clock) is disclosed with a permanently-sealed vacuum package containing a source of ytterbium (Yb) ions and an octupole ion trap. The source of Yb ions is a micro-hotplate which generates Yb atoms which are then ionized by a ultraviolet light-emitting diode or a field-emission electron source. The octupole ion trap, which confines the Yb ions, is formed from suspended electrodes on a number of stacked-up substrates. A microwave source excites a ground-state transition frequency of the Yb ions, with a frequency-doubled vertical-external-cavity laser (VECSEL) then exciting the Yb ions up to an excited state to produce fluorescent light which is used to tune the microwave source to the ground-state transition frequency, with the microwave source providing a precise frequency output for the ion clock.