Abstract: In the context of gate-model quantum computing, atoms (or polyatomic molecules) are excited to respective Rydberg states to foster intra-gate interactions. Rydberg states with relatively high principal quantum numbers are used for relatively distant intra-gate interactions and require relatively great inter-gate separations to avoid error-inducing inter-gate interactions. Rydberg states with relatively low principal quantum numbers can be used for intra-gate interactions over relatively short intra-gate distances and require relatively small inter-gate separations to avoid error-inducing inter-gate interactions. The relatively small inter-gate separations provide opportunities for parallel gate executions, which, in turn, can provide for faster execution of the quantum circuit constituted by the gates.

Abstract: A vacuum cell including a vacuum chamber, a first bond, and a second bond is described. The first bond affixes a first portion of the vacuum cell to a second portion of the vacuum cell. The first bond has a first bonding temperature and a first debonding temperature greater than the first bonding temperature. The second bond affixes a third portion of the vacuum cell to a fourth portion of the vacuum cell. The second bond has a second bonding temperature and a second debonding temperature. The second bonding temperature is less than the first debonding temperature.

Abstract: A trap for quantum particles, e.g., cesium atoms, is formed using electromagnetic radiation (EMR) of different wavelengths (concurrently and/or at different times). “Red-detuned” EMR, having a trap wavelength longer than a resonant wavelength for a quantum particle is “attracting” and, so, can be used to form the array trap while loading atoms into the array trap. “Blue-detuned” EMR, having a trap wavelength shorter than the resonant wavelength can repel atoms into dark areas away from the EMR peaks so that the atoms are not disturbed by interference carried by the EMR; accordingly, the blue-detuned EMR is used to form the array trap during quantum-circuit execution. Red and blue detuned EMR are used together to form deeper traps that can be used to detect vacant atom sites. Other combinations of trap wavelengths can also be used.

Abstract: A trap for quantum particles, e.g., cesium atoms, is formed using electromagnetic radiation (EMR) of different wavelengths (concurrently and/or at different times). “Red-detuned” EMR, having a trap wavelength longer than a resonant wavelength for a quantum particle is “attracting” and, so, can be used to form the array trap while loading atoms into the array trap. “Blue-detuned” EMR, having a trap wavelength shorter than the resonant wavelength can repel atoms into dark areas away from the EMR peaks so that the atoms are not disturbed by interference carried by the EMR; accordingly, the blue-detuned EMR is used to form the array trap during quantum-circuit execution. Red and blue detuned EMR are used together to form deeper traps that can be used to detect vacant atom sites. Other combinations of trap wavelengths can also be used.

Abstract: In the context of gate-model quantum computing, atoms (or polyatomic molecules) are excited to respective Rydberg states to foster intra-gate interactions. Rydberg states with relatively high principal quantum numbers are used for relatively distant intra-gate interactions and require relatively great inter-gate separations to avoid error-inducing inter-gate interactions. Rydberg states with relatively low principal quantum numbers can be used for intra-gate interactions over relatively short intra-gate distances and require relatively small inter-gate separations to avoid error-inducing inter-gate interactions. The relatively small inter-gate separations provide opportunities for parallel gate executions, which, in turn, can provide for faster execution of the quantum circuit constituted by the gates.

Abstract: A vacuum cell provides for electric field control within an ultra-high vacuum (UHV) for cold-neutral-atom quantum computing and other quantum applications. Electrode assemblies extend through vacuum cell walls. Prior to cell assembly, contacts are bonded to respective locations on the ambient-facing surfaces of the walls. Trenches are formed in the vacuum-facing surfaces of walls and via holes are formed, extending from trenches through the wall and into the contacts. Plating conductive material into the trenches and via holes forms the electrodes and vias. The electrodes are contained by the trenches and do not extend beyond the trenches so as to avoid interfering with the bonding of components to the vacuum-facing surfaces of the walls. The vias extend into the contacts to ensure good electrical contact. An electric-field controller applies electric potentials to the electrodes (via the contacts) to control electric fields within the vacuum.

Abstract: When a molecule is lost from a site of a qubit array, the site can be identified as a “target” site. A target site can be reloaded by transporting a molecule from a reservoir at least two millimeters to the target site. Alternatively, in response to the identifying, a molecule that has been transferred from the reservoir to a qubit-array region including the qubit array can be transferred to the target site. Quantum-logic language (QLL) programs can continue qubit operations on the array during transfers from the reservoir to the qubit region. Such operations can also continue during transfer from within the qubit region to a target site; in some cases, these latter operations are limited to sections of the qubit array not including a target site.