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FOPRA Experiment 104: The Josephson Parametric Amplifier (JPA) (QST-EX)

Course 0000100104 in SS 2024

General Data

Course Type practical training
Semester Weekly Hours 1 SWS
Organisational Unit Technical Physics
Lecturers Kedar Honasoge
Wun Kwan Yam
Responsible/Coordination: Rudolf Gross

Further Information

Courses are together with exams the building blocks for modules. Please keep in mind that information on the contents, learning outcomes and, especially examination conditions are given on the module level only – see section "Assignment to Modules" above.

additional remarks In superconducting quantum circuits, such as quantum bits, information is processed and transferred in the form of microwave quantum signals. Moreover, at the end of quantum information protocols, these signals have to be recorded by room temperature electronic devices. Since microwave quantum signals typically consist of very few photons, they must be amplified in order to achieve reasonable signal-to-noise ratios. Therefore, low-noise amplification of quantum signals is crucial. Modern low-noise microwave amplifiers are built upon superconducting Josephson parametric devices, such as a flux-driven Josephson Parametric Amplifier (JPA), which allows to reach the standard quantum limit of amplification and even go beyond it. The current JPA is formed by a superconducting quantum interference device (SQUID) combined with a superconducting coplanar waveguide resonator. The combined system acts as a tunable nonlinear microwave resonator, whose frequency can be varied in-situ via an external magnetic field. A mechanical analogue would be a pendulum of variable length, allowing one to tune its eigenfrequency. Tunability of the nonlinear microwave resonator can be exploited to parametrically pump the JPA via application of a strong microwave signal at twice the resonant frequency. This, in turn, can result in a strong parametric amplification of weak quantum signals incident at the JPA. The same parametric amplification mechanism can be exploited further for generation of genuine quantum signals in the form of squeezed vacuum states.
Links Course documents
TUMonline entry
TUMonline registration for 29: 29.04.2024-04.05.2024 (Mittwoch: Tag der Arbeit), 30: 06.05.2024-11.05.2024 (Donnerstag: Christi Himmelfahrt)
TUMonline registration for 33: 27.05.2024-01.06.2024 (Donnerstag: Fronleichnam, Schulen: Pfingstferien), 34: 03.06.2024-08.06.2024
TUMonline registration for 35: 10.06.2024-15.06.2024, 36: 17.06.2024-22.06.2024
TUMonline registration for 37: 24.06.2024-29.06.2024, 38: 01.07.2024-06.07.2024
TUMonline registration for 39: 08.07.2024-13.07.2024, 40: 15.07.2024-20.07.2024
TUMonline registration for 41: 22.07.2024-27.07.2024, 42: 29.07.2024-03.08.2024
TUMonline registration for 43: 05.08.2024-10.08.2024, 44: 12.08.2024-17.08.2024 (Donnerstag: Maria Himmelfahrt)
TUMonline registration for 45: 19.08.2024-24.08.2024, 46: 26.08.2024-31.08.2024
TUMonline registration for 47: 02.09.2024-07.09.2024, 48: 09.09.2024-14.09.2024
TUMonline registration for 49: 16.09.2024-21.09.2024, 50: 23.09.2024-28.09.2024
TUMonline registration for 31: 13.05.2024-18.05.2024, 32: 21.05.2024-25.05.2024 (Montag: Pfingstmontag, Schulen: Pfingstferien)
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