Observable geometric phase induced by a cyclically evolving dissipative process

Abstract

In [1] a new way to generate an observable geometric phase on a quantum system by means of a completely incoherent phenomenon has been proposed. The basic idea is to force the ground state of the system to evolve ciclically by "adiabatically" manipulating the environment with which it interacts. The specific scheme analyzed in [1], consisting of a multilevel atom interacting with a broad-band squeezed vacuum bosonic bath whose squeezing parameters are smoothly changed in time along a closed loop, is here solved in a more direct way. This new solution emphasizes how the geometric phase on the ground state of the system is indeed due to a purely incoherent dynamics.

Journeys from quantum optics to quantum technology

“…The basic idea was to force the ground state of the system to evolve cyclically by adiabatically manipulating the environment with which it interacts. As a specific scheme, we indeed analyzed a multilevel atom interacting with a broadband squeezed vacuum bosonic bath whose squeezing parameters r and ϕ are smoothly changed in time along a closed loop [165,166]. The interesting feature of such scheme is the the fact that the geometric phase imprinted on the ground state of the system is due to a purely incoherent engineered dynamics.…”

Time-dependent decoherence-free subspace

“…It has been shown in Refs. [19,20] that the decoherencefree evolution can be achieved by adiabatically changing the squeezing phase. Comparing with Ref.…”

Decoherence-free evolution of time-dependent superposition states of two-level systems and thermal effects

“…Rightly connected to the engineering Hamiltonian program [2], the reservoir engineering has been developed for trapped ions [3,4] and atomic two-level (T L) systems [5]. Recently, under the assumption of a squeezed engineered reservoir, a way to observe the adiabatic geometric phase acquired by a protected state has been proposed [6][7][8] under the assumption of an adiabatic evolution of the system-reservoir parameters. It is worth mentioning recent results on the possibility to drive an open many-body quantum system into a given pure state by an appropriate design of the system-reservoir coupling [9,10].…”

“…In this paper we detail the general recipe presented in Ref. [11] showing how to build nonadiabatic coherent evolutions of a two-level ion trapped into a leaky cavity, in contrast with the applications of the engineering reservoir technique which require adiabatic conditions [6][7][8]. Furthermore, we show how to implement the proposal of Ref.…”