Observation of quantum many-body effects due to zero point fluctuations in superconducting circuits

Seminar
QUEST Center event
Yes
Speaker
Nicolas Roch
Date
18/05/2020 - 15:30 - 13:30Add to Calendar 2020-05-18 13:30:00 2020-05-18 15:30:00 Observation of quantum many-body effects due to zero point fluctuations in superconducting circuits Note: The colloquium will take place via ZOOM:  https://zoom.us/j/4459928099 Meeting ID: 445 992 8099   Electromagnetic fields possess zero point fluctuations which lead to observable effects such as the Lamb shift and the Casimir effect. In the traditional quantum optics domain, these corrections remain perturbative due to the smallness of the fine structure constant. To provide a direct observation of non-perturbative effects driven by zero point fluctuations in an open quantum system we wire a highly non-linear Josephson junction to a high impedance transmission line, allowing large phase fluctuations across the junction [1]. Consequently, the resonance of the former acquires a relative frequency shift that is orders of magnitude larger than for natural atoms. Detailed modeling confirms that this renormalization is non-linear and quantum. Remarkably, the junction transfers its non-linearity to about thirty environmental modes, a striking back-action effect that transcends the standard Caldeira-Leggett paradigm. This work opens many exciting prospects for longstanding quests such as the tailoring of many-body Hamiltonians in the strongly non-linear regime, the observation of Bloch oscillations,or the development of high-impedance qubits.   [1] Léger, S., Puertas-Martínez, J., Bharadwaj, K. et al. Observation of quantum many-body effects due to zero point fluctuations in superconducting circuits. Nat Commun 10, 5259 (2019) Zoom המחלקה לפיזיקה physics.dept@mail.biu.ac.il Asia/Jerusalem public
Place
Zoom
Abstract

Note: The colloquium will take place via ZOOM:  https://zoom.us/j/4459928099

Meeting ID: 445 992 8099
 

Electromagnetic fields possess zero point fluctuations which lead to observable effects such as the Lamb shift and the Casimir effect. In the traditional quantum optics domain, these corrections remain perturbative due to the smallness of the fine structure constant. To provide a direct observation of non-perturbative effects driven by zero point fluctuations in an open quantum system we wire a highly non-linear Josephson junction to a high impedance transmission line, allowing large phase fluctuations across the junction [1]. Consequently, the resonance of the former acquires a relative frequency shift that is orders of magnitude larger than for natural atoms. Detailed modeling confirms that this renormalization is non-linear and quantum. Remarkably, the junction transfers its non-linearity to about thirty environmental modes, a striking back-action effect that transcends the standard Caldeira-Leggett paradigm. This work opens many exciting prospects for longstanding quests such as the tailoring of many-body Hamiltonians in the strongly non-linear regime, the observation of Bloch oscillations,or the development of high-impedance qubits.

 

[1] Léger, S., Puertas-Martínez, J., Bharadwaj, K. et al. Observation of quantum many-body effects due to zero point fluctuations in superconducting circuits. Nat Commun 10, 5259 (2019)

תאריך עדכון אחרון : 10/05/2020