Abstract: An apparatus comprises a support structure and one or more first optical components on the support structure that communicatively couple with a first endpoint. The one or more first optical components are configured to output and receive optical signals that travel over a free space medium to establish a secure link between the first endpoint and a second endpoint.

Abstract: A method and system for large scale Vertical-Cavity Surface-Emitting Laser (VCSEL) binning from wafers to be compatible with a Clock-Data Recovery Unit (CDRU) and/or a VCSEL driver are provided. An illustrative method of binning is provided that includes: for at least a portion of VCSELs on a wafer, measuring a set of representative parameters of the VCSELs, of predetermined DC or small-signal values, and sorting the measured VCSELs into clusters according to the measured set of representative parameters of the VCSELs; further sorting the clusters into sub-groups that comply with specifications of the VCSEL driver; and providing a feedback signal to the CDRU for equalizing control signals provided to the VCSEL driver.

Abstract: Various embodiments of the present disclosure are directed to accessing a quantum communication channel undetected and/or characterizing this communication channel based upon attempted access. An example method includes accessing a quantum communication channel transmitting one or more qubits. The method includes the introduction of a noise signal to the quantum communication channel and then applying in its absence one or more weak or variable-strength measurements to the quantum communication channel. A strength of at least one measurement of the one or more measurements is based at least in part upon the current noise signal. The method further includes obtaining information associated with the one or more qubits based on the one or more measurements.

Abstract: Embodiments are disclosed for providing quantum-classical hybrid security. An example system includes a hybrid quantum-classical transmitter device. The hybrid quantum-classical transmitter device includes a classical transmitter and a quantum transmitter. The classical transmitter is configured to generate data based on a cryptography technique. The classical transmitter is also configured to generate a classical bitstream representation of the data, where the classical bitstream is configured for transmission via an optical communication channel. The quantum transmitter is configured to embed one or more qubits into the classical bitstream to generate a hybrid quantum-classical bitstream for transmission via the optical communication channel.

Abstract: Bi-directional quantum interconnects are provided that include a first communication module and a second communication module. The first communication module includes a first quantum transmitter and a first quantum receiver, and the second communication module includes a second quantum transmitter and a second quantum receiver. The example interconnect further includes a first communication medium communicably coupling the first communication module and the second communication module such that communication is provided between the first quantum transmitter and the second quantum receiver and between the second quantum transmitter and the first quantum receiver via the first communication medium. The first quantum transmitter and the second quantum transmitter generate qubits having first and second quantum characteristics, respectively, to allow for bi-directional quantum communication over a common channel.

Abstract: High bandwidth (e.g., >100 GHz) modulators and methods of fabricating such are provided. An optical modulator comprises transmission lines configured to provide a respective radio frequency signal to a respective plurality of segmented capacitive loading electrodes; pluralities of segmented capacitive loading electrodes in electrical communication with a respective one of the transmission lines and in electrical communication with an interface layer of a semiconductor waveguide structure; and the semiconductor waveguide structure. The semiconductor waveguide structure is configured to modulate an optical signal propagating therethrough based at least in part on the respective radio frequency signal. The semiconductor waveguide structure comprises the interface layer, which (a) comprises a semiconductor material and (b) is configured such that an interface resistance of the modulator is ?4 Ohms.

Abstract: High bandwidth (e.g., > 100 GHz) modulators and methods of fabricating such are provided. An EAM comprises a waveguide mesa comprising a continuous multi-quantum well (MQW) layer; a plurality of electrode segments disposed on the waveguide mesa; and a microstrip transmission line disposed on an insulating material layer and in electrical communication with the plurality of electrode segments via conducting bridges. The waveguide mesa comprises alternating active sections and passive sections. An electrode segment of the plurality of electrodes is disposed on a respective one of the active sections. Portions of the continuous MQW layer disposed in each of the active sections having an energy gap defining an active energy gap value. Portions of the continuous MQW layer disposed in each of the passive sections having an energy gap defining an passive energy gap value. The active energy gap value is less than the passive energy gap value.

Abstract: An apparatus comprises a support structure and one or more first optical components on the support structure that communicatively couple with a first endpoint. The one or more first optical components are configured to output and receive optical signals that travel over a free space medium to establish a secure link between the first endpoint and a second endpoint.

Abstract: High bandwidth (e.g., > 100 GHz) modulators and methods of fabricating such are provided. An optical modulator comprises transmission lines configured to provide a respective radio frequency signal to a respective plurality of segmented capacitive loading electrodes; pluralities of segmented capacitive loading electrodes in electrical communication with a respective one of the transmission lines and in electrical communication with an interface layer of a semiconductor waveguide structure; and the semiconductor waveguide structure. The semiconductor waveguide structure is configured to modulate an optical signal propagating therethrough based at least in part on the respective radio frequency signal. The semiconductor waveguide structure comprises the interface layer, which (a) comprises a semiconductor material and (b) is configured such that an interface resistance of the modulator is ? 4 Ohms.

Abstract: A method and system for large scale Vertical-Cavity Surface-Emitting Laser (VCSEL) binning from wafers to be compatible with a Clock-Data Recovery Unit (CDRU) and/or a VCSEL driver are provided. An illustrative method of binning is provided that includes: for at least a portion of VCSELs on a wafer, measuring a set of representative parameters of the VCSELs, of predetermined DC or small-signal values, and sorting the measured VCSELs into clusters according to the measured set of representative parameters of the VCSELs; further sorting the clusters into sub-groups that comply with specifications of the VCSEL driver; and providing a feedback signal to the CDRU for equalizing control signals provided to the VCSEL driver.

Abstract: A method and system for analyzing Vertical-Cavity Surface-Emitting Lasers (VCSELs) on a wafer are provided. An illustrative method of is provided that includes: applying a stimulus to each of the plurality of VCSELs on the wafer; measuring, for each of the plurality of VCSELs, two or more VCSEL parameters responsive to the stimulus; correlating the measured two or more VCSEL parameters to define a value of a common performance characteristic; and identifying clusters of VCSELs having similar values of the common performance characteristic. The clusters of VCSELs may be determined to collectively meet or not meet an optical performance requirement defined for the VCSELs on the wafer.