相关论文: Multiphoton transitions in a macroscopic quantum t…

We report on fluctuations in the electron system, Cooper pairs and quasiparticles, of a superconducting aluminium film. The superconductor is exposed to pair-breaking photons (1.54 THz), which are coupled through an antenna. The change in…

We suggest a scheme to probe critical phenomena at a quantum phase transition (QPT) using the quantum correlation of two photonic modes simultaneously coupled to a critical system. As an experimentally accessible physical implementation, a…

The controllability of current quantum technologies allows to implement spin-boson models where two-photon couplings are the dominating terms of light-matter interaction. In this case, when the coupling strength becomes comparable with the…

The statistics photons in the resonance fluorescence of a qubit excited by microwave and radio-frequency (RF) fields have been studied. It has been established that the coherent dissipative dynamics of the qubit with allowance for…

We perform two-tone spectroscopy on quantum circuits, where high-frequency radiation is generated by a voltage-biased superconductor-normal-superconductor Josephson junction and detection is carried out by an ancillary microwave resonator.…

A microscopic model of a Josephson junction between two superconducting plates is proposed and analysed. For this model, the nonequilibrium steady state of the total system is explicitly constructed and its properties are analysed. In…

Quantum information science is driving progress in a vast number of scientific and technological areas that cover molecular spectroscopy and matter-light interactions in general. In these fields, the ability to generate quantum…

The purpose of this paper is to present a mathematical framework for analyzing the response of quantum linear systems driven by multi-photon states. Both the factorizable (namely, no correlation among the photons in the channel) and…

We identify the different contributions to quantum interference in a mesoscopic metallic loop in contact with two superconducting electrodes. At low temperature, a flux-modulated Josephson coupling is observed with strong damping over the…

Quantum entanglement, one of the defining features of quantum mechanics, has been demonstrated in a variety of nonlinear spin-like systems. Quantum entanglement in linear systems has proven significantly more challenging, as the intrinsic…

Recent experiments claiming formation of quantum superposition states in near macroscopic sys- tems raise the question of how the sizes of general quantum superposition states in an interacting system are to be quantified. We propose here a…

We consider a Josephson junction formed by a quantum dot connected to two bulk superconductors in presence of Coulomb interaction and coupling to both an electromagnetic environment and a finite density of electronic quasi-particles. In the…

We propose a method to transfer macroscopically superposed states between two optical cavities mediated by a mechanical oscillator, which works in a nonlinear regime of optomechanical interaction. Our approach relies on the phonon-induced…

The frequency dependence of the peak-valley pairs occurring in the magnetoresistivity of a two-dimensional electron system under enhanced microwave irradiation, which are considered to associate with multiphoton processes, is examined in…

We examine the competition among one- and two-photon processes in an ultra-cold, three-level atom undergoing cascade transitions as a result of its interaction with a bimodal cavity. We show parameter domains where two-photon transitions…

We have studied two-photon transitions from Upsilon(3S) decays recorded by the CLEO-III detector in exclusive events with two photons and either two electrons or two muons. We obtain precision measurements of the chi_b(2P_J) masses for J=2…

For dissipation-free photon-photon interaction at the single photon level, we analyze one-photon transition and two-photon transition induced by photon pairs in three-level atoms using two-photon wavefunctions. We show that the two-photon…

We consider a spin-boson model in which a spin 1 system is coupled to an oscillator. A unitary transformation is applied which allows a separation of terms responsible for the Bloch-Siegert shift, and terms responsible for the level…

We have observed multi-photon resonances in a system with a spin 3/2 irradiated simultaneously by a multiple pulse radiofrequency sequence and a low frequency field swept in the range 0-80 kHz. The used excitation scheme allowed us to…

In the classical Josephson effect the phase difference across the junction is well defined, and the supercurrent is reduced only weakly by phase diffusion. For mesoscopic junctions with small capacitance the phase undergoes large quantum…