A device comprises a U-shaped cell configured to contain a quantum gas, a first waveguide coupled to an inlet of the U-shaped cell, and a second waveguide coupled to an outlet of the U-shaped cell. The device also comprises a multi-layer substrate including transmitter and receiver antennas that are aligned with the first and second waveguides, respectively, the substrate including a network of metal layers coupled to the transmitter and receiver antennas. The device also includes transmitter and receiver dies coupled to the transmitter and receiver antennas, respectively, by way of the network of metal layers, the substrate positioned between the U-shaped cell and the transmitter and receiver dies.

A radio-frequency antenna through which a high amount of current can be efficiently passed even at a radio-frequency level for plasma generation, as well as a plasma processing device utilizing the radio-frequency antenna. A radio-frequency antenna includes a metal fiber sheet. A plasma processing device includes: a vacuum container including a wall having an opening; a radio-frequency antenna including a metal fiber sheet and located at the opening; and a dielectric protection plate located closer to the interior of the vacuum container than the radio-frequency antenna and configured to close the opening in a gas-tight manner. The radio-frequency antenna including a metal fiber sheet has a larger surface area and a lower impedance to a radio-frequency current than a radio-frequency antenna including a metal plate having the same outer shape. Therefore, it allows a radio-frequency current commonly used for plasma generation to be more efficiently passed through in large amounts.

A device comprises a U-shaped cell configured to contain a quantum gas, a first waveguide coupled to an inlet of the U-shaped cell, and a second waveguide coupled to an outlet of the U-shaped cell. The device also comprises a multi-layer substrate including transmitter and receiver antennas that are aligned with the first and second waveguides, respectively, the substrate including a network of metal layers coupled to the transmitter and receiver antennas. The device also includes transmitter and receiver dies coupled to the transmitter and receiver antennas, respectively, by way of the network of metal layers, the substrate positioned between the U-shaped cell and the transmitter and receiver dies.

A device comprises a U-shaped cell configured to contain a quantum gas, a first waveguide coupled to an inlet of the U-shaped cell, and a second waveguide coupled to an outlet of the U-shaped cell. The device also comprises a multi-layer substrate including transmitter and receiver antennas that are aligned with the first and second waveguides, respectively, the substrate including a network of metal layers coupled to the transmitter and receiver antennas. The device also includes transmitter and receiver dies coupled to the transmitter and receiver antennas, respectively, by way of the network of metal layers, the substrate positioned between the U-shaped cell and the transmitter and receiver dies.