相关论文: What is Quantum in Quantum Pumping: The Role of Ph…

A selected set of topics in quantum phase transition is discussed. It includes dissipative quantum phase transitions, the role of disorder, and the relevance of quantum phase transition to measurement theory in quantum mechanics.

After reviewing the role of phase in quantum mechanics, I discuss, with the aid of a number of unpublished documents, the development of quantum phase operators in the 1960's. Interwoven in the discussion are the critical physics questions…

We study spontaneous quantum coherence in an out of equilibrium system, coupled to multiple baths describing pumping and decay. For a range of parameters describing coupling to, and occupation of the baths, a stable steady-state condensed…

We study electron pumping through a system of barriers, whose heights are deformed adiabatically. We derive a simple formula for the pumped charge $Q$ in terms of the total reflection and transmission amplitudes and phases. The pumped…

We derived a general and exact expression of current for quantum parametric charge pumps in the non-adiabatic regime at finite pumping frequency and finite driving amplitude. The non-perturbative theory predicts a remarkable plateau…

Current can be pumped through a closed system by changing parameters (or fields) in time. Linear response theory (the Kubo formula) allows to analyze both the charge transport and the associated dissipation effect. We make a distinction…

Quantum operations represented by completely positive maps encompass many of the physical processes and have been very powerful in describing quantum computation and information processing tasks. We introduce the notion of relative phase…

In this Letter, we consider the adiabatic charge transport through a normal mesoscopic sample sandwiched by superconductors without modulation of local chemical potentials. The deformation of coherent quasiparticles in the normal metal in…

Even though quantum pumping is a very promising field, it has unfortunately not been unambiguously experimentally detected. The reason being that in the experiments the rectification effect overshadows the pumped current. One of the better…

We study two different parametric pumps for interacting quantum wires, one for pumping spin currents, the other for charge currents. We find that the spin or charge pumped per cycle has a non-universal crossover, depending on pumping…

Quantum mechanical wave functions have phases. These phases either initial or acquired during time evolution usually do not enter the final expressions for observable physical quantities. Nevertheless in many cases the observable physical…

We examine adiabatic quantum pumping generated by an oscillating scatterer embedded in a one-dimensional ballistic ring and compare it with pumping caused by the same scatterer connected to external reservoirs. The pumped current for an…

The charge current pumped adiabatically through a deformable quantum dot is studied within the Green's function approach. Differently from the non-deformable case, the current shows an undefined parity with respect to the pumping phase…

We discuss some seemingly paradoxical yet valid effects of quantum physics in information processing. Firstly, we argue that the act of ``doing nothing'' on part of an entangled quantum system is a highly non-trivial operation and that it…

A sweep through a quantum phase transition by means of a time-dependent external parameter (e.g., pressure) entails non-equilibrium phenomena associated with a break-down of adiabaticity: At the critical point, the energy gap vanishes and…

In this mainly pedagogical article, we discuss under what circumstances measurements play a special role in quantum processes. In particular we discuss the following facts which appear to be a common area of confusion: i) from a fundamental…

Quantum phase estimation is fundamental to advancing quantum science and technology. While much of the research has concentrated on estimating a single phase, the simultaneous estimation of multiple phases can yield significantly enhanced…

We use the equations of motion of non-interacting electrons in a one-dimensional system to numerically study different aspects of charge pumping. We study the effects of the pumping frequency, amplitude, band filling and finite bias on the…

The topological property in one dimension (1D) is protected by symmetry. Based on a concrete model, we show that since a 1D topological model usually contain two of the three Pauli matrix, the left one automatically become the protecting…

Studies of strongly nonlinear dynamical systems such as turbulent flows call for superior computational prowess. With the advent of quantum computing, a plethora of quantum algorithms have demonstrated, both theoretically and…