Displacement of Propagating Squeezed Microwave States

Fedorov, Kirill G.; Zhong, L.; Pogorzalek, Stefan; Eder, Peter; Fischer, Michael; Goetz, Jan; Xie, Edwar; Wulschner, F.; Inomata, K.; Yamamoto, Tsuyoshi; Nakamura, Y.; Candia, Roberto Di; Heras, U. Las; Sanz, Mikel; Solano, E.; Menzel, E. P.; Deppe, Frank; Marx, Achim; Gross, Rudolf

doi:10.1103/physrevlett.117.020502

Cited by 65 publications

(53 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The particular digitizing procedure to calculate all correction moments I n 1 I m 2 Q k 1 Q 2 up to fourth order (0 ≤ n + m + k + ≤ 4 with n, m, k, ∈ N 0 ) is described in detail in Ref. 19. From these calculations, we extract the signal moments (â † ) nâm .…”

Section: Experimental Setup and Characterization Of The Jpa Samplementioning

confidence: 99%

“…Additionally, we calculate the variance of an amplified thermal fields [see Fig. S4 (b)], which is relevant for reconstruction setups [18,19] using parametric amplifiers as preamplifiers. To calculate the photon number variance of an attenuated thermal field, we use the beam splitter model depicted in Fig.…”

Section: Correlators For Attenuated and Amplified Microwave Fieldsmentioning

confidence: 99%

“…19. Both Josephson parametric amplifier (JPA) samples were designed and fabricated at NEC Smart Energy Research Laboratories, Japan and RIKEN, Japan.…”

Section: Experimental Setup and Characterization Of The Jpa Samplementioning

confidence: 99%

“…In this context, an important aspect is the generation of propagating thermal microwaves using thermal emitters [15][16][17]. These emitters can be spatially separated from the setup components used for manipulation and detection [18,19], which allows one to individually control the emitter and the setup temperature. Due to the low energy of microwave photons, the detection of these fields typically requires the use of nearquantum-limited amplifiers [20][21][22][23], cross-correlation detectors [17, 18, 24], or superconducting qubits [25][26][27][28].…”

mentioning

confidence: 99%

See 3 more Smart Citations

Photon Statistics of Propagating Thermal Microwaves

et al. 2017

Self Cite

View full text Add to dashboard Cite

In experiments with superconducting quantum circuits, characterizing the photon statistics of propagating microwave fields is a fundamental task. We quantify the n 2 + n photon number variance of thermal microwave photons emitted from a black-body radiator for mean photon numbers 0.05 n 1.5. We probe the fields using either correlation measurements or a transmon qubit coupled to a microwave resonator. Our experiments provide a precise quantitative characterization of weak microwave states and information on the noise emitted by a Josephson parametric amplifier.As propagating electromagnetic fields in general [1][2][3], propagating microwaves with photon numbers on the order of unity are essential for quantum computation [4,5], communication [6], and illumination [7][8][9][10] protocols. Because of their omnipresence in experimental setups, the characterization of thermal states is especially relevant for many applications [11][12][13][14]. Specifically in the microwave regime, sophisticated experimental techniques for their generation at cryogenic temperatures, their manipulation, and detection have been developed in recent years. In this context, an important aspect is the generation of propagating thermal microwaves using thermal emitters [15][16][17]. These emitters can be spatially separated from the setup components used for manipulation and detection [18,19], which allows one to individually control the emitter and the setup temperature. Due to the low energy of microwave photons, the detection of these fields typically requires the use of nearquantum-limited amplifiers [20][21][22][23], cross-correlation detectors [17, 18, 24], or superconducting qubits [25][26][27][28].The unique nature of propagating fields is reflected in their photon statistics, which is described by a probability distribution either in terms of the number states or in terms of its moments. The former were studied by coupling the field to an atom or qubit and measuring the coherent dynamics [29][30][31] or by spectroscopic analysis [32]. The moment-based approach requires knowledge on the average photon number n and its variance Var(n) = n 2 − n 2 to distinguish many states of interest. To this end, the second-order correlation function g (2) (τ ) has been measured to analyze the photon statistics of thermal [33][34][35] or quantum [36][37][38] emitters ever since the ground-breaking experiments of Hanbury Brown and Twiss [39,40]. While these experiments use the time delay τ as control parameter, at microwave frequencies the photon number n can be controlled conveniently [15,32,[41][42][43][44]. In the specific case of a thermal field at frequency ω, the Bose-Einstein distribution yields n(T ) = [exp( ω/k B T ) − 1] −1 and Var(n) = n 2 + n, which can be controlled by the temperature T of the emitter. In practice, one wants to distinguish this relation from both the classical limit Var(n) = n 2 and the Poissonian behavior Var(n) = n characteristic for coherent states [41] or shot noise [45,46]. Hence, as shown in Fig. 1, the most relev...

show abstract

Section: Experimental Setup and Characterization Of The Jpa Samplementioning

confidence: 99%

Section: Correlators For Attenuated and Amplified Microwave Fieldsmentioning

confidence: 99%

“…19. Both Josephson parametric amplifier (JPA) samples were designed and fabricated at NEC Smart Energy Research Laboratories, Japan and RIKEN, Japan.…”

Section: Experimental Setup and Characterization Of The Jpa Samplementioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Photon Statistics of Propagating Thermal Microwaves

et al. 2017

Self Cite

View full text Add to dashboard Cite

show abstract

“…Following the path of Yurke's et al work in the late 1980s [1][2][3], several designs of Josephson junction-based parametric amplifiers (JPAs) have been introduced [4][5][6][7][8][9][10][11]. In addition to high-fidelity superconducting qubit readout leading to the observation of quantum jumps [12,13], this new generation of near quantumlimited amplifiers have opened up new experimental possibilities such as the creation and tomography of squeezed microwave light [14][15][16], and detailed weak measurement experiments [17][18][19]. JPAs are now ubiquitous in current superconducting circuit experiments, and applications in other research communities are growing [20][21][22][23].…”

Section: Introductionmentioning

confidence: 99%

Effect of Higher-Order Nonlinearities on Amplification and Squeezing in Josephson Parametric Amplifiers

et al. 2017

View full text Add to dashboard Cite

Single-mode Josephson junction-based parametric amplifiers are often modeled as perfect amplifiers and squeezers. We show that, in practice, the gain, quantum efficiency, and output field squeezing of these devices are limited by usually neglected higher-order corrections to the idealized model. To arrive at this result, we derive the leading corrections to the lumped-element Josephson parametric amplifier of three common pumping schemes: monochromatic current pump, bichromatic current pump, and monochromatic flux pump. We show that the leading correction for the last two schemes is a single Kerr-type quartic term, while the first scheme contains additional cubic terms. In all cases, we find that the corrections are detrimental to squeezing. In addition, we show that the Kerr correction leads to a strongly phase-dependent reduction of the quantum efficiency of a phase-sensitive measurement. Finally, we quantify the departure from ideal Gaussian character of the filtered output field from numerical calculation of third and fourth order cumulants. Our results show that, while a Gaussian output field is expected for an ideal Josephson parametric amplifier, higher-order corrections lead to non-Gaussian effects which increase with both gain and nonlinearity strength. This theoretical study is complemented by experimental characterization of the output field of a flux-driven Josephson parametric amplifier. In addition to a measurement of the squeezing level of the filtered output field, the Husimi Q-function of the output field is imaged by the use of a deconvolution technique and compared to numerical results. This work establishes nonlinear corrections to the standard degenerate parametric amplifier model as an important contribution to Josephson parametric amplifier's squeezing and noise performance.

show abstract

The Future: From Q‐demonstrations to Q‐technologies

Bachor

Ralph

2019

A Guide to Experiments in Quantum Optics

View full text Add to dashboard Cite

Displacement of Propagating Squeezed Microwave States

Cited by 65 publications

References 31 publications

Photon Statistics of Propagating Thermal Microwaves

Photon Statistics of Propagating Thermal Microwaves

Effect of Higher-Order Nonlinearities on Amplification and Squeezing in Josephson Parametric Amplifiers

The Future: From Q‐demonstrations to Q‐technologies

Contact Info

Product

Resources

About