Lamb-Shift Enhancement and Detection in Strongly Driven Superconducting Circuits

Gramich, Vera; Gasparinetti, Simone; Solinas, Paolo; Ankerhold, Joachim

doi:10.1103/physrevlett.113.027001

Cited by 17 publications

(17 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Further, in the context of superconducting devices, strong driving with external microwaves has become an interesting field on its own [36][37][38][39]. For future experimental realizations in this direction, predictions of nonperturbative phenomena may thus become very important.…”

Section: Discussionmentioning

confidence: 99%

Work and heat for two-level systems in dissipative environments: Strong driving and non-Markovian dynamics

et al. 2015

View full text Add to dashboard Cite

Work, moments of work and heat flux are studied for the generic case of a strongly driven twolevel system immersed in a bosonic heat bath in domains of parameter space where perturbative treatments fail. This includes particularly the interplay between non-Markovian dynamics and moderate to strong external driving. Exact data are compared with predictions from weak coupling approaches. Further, the role of system-bath correlations in the initial thermal state and their impact on the heat flux are addressed. The relevance of these results for current experimental activities on solid state devices is discussed.

show abstract

Section: Discussionmentioning

confidence: 99%

Work and heat for two-level systems in dissipative environments: Strong driving and non-Markovian dynamics

et al. 2015

View full text Add to dashboard Cite

show abstract

“…the Born (weak coupling) and Markov (local in time) approximations for the time evolution are performed. In this way, the Floquet-Markov Master equation [29,53,57,62,[64][65][66][67][68] is obtained:…”

Section: Appendix A: Floquet-markov Master Equationmentioning

confidence: 99%

Amplitude tuning of steady-state entanglement in strongly driven coupled qubits

2018

View full text Add to dashboard Cite

In this work we report on a new mechanism to generate dissipative steady state entanglement in two coupled qubits driven by strong periodic ac fields. We show that steady entanglement can be generated at one side of a multiphoton resonance between a non-entangled ground state and an entangled excited state. The degree of entanglement can be tuned as a function of the amplitude of the periodic drive. A rich dynamic behavior with creation, death and revival of entanglement can be observed for certain parameter regimes, accessible in current experimental devices.The generation and stabilization of entanglement is one of the main challenges in quantum information applications. In recent years strategies based on the creation of steady state entanglement through engineered dissipation have been discussed theoretically [1-3] and demonstrated in experiments [4][5][6][7][8][9][10]. In this scheme, the system of interest is driven by external fields and coupled to a reservoir, developing a nontrivial non-equilibrium dynamics that leads to a highly entangled steady state. The effective relaxation rates can be tuned by adequately designing the quantum reservoir, the system-reservoir couplings or the driving protocols. Experimental demonstrations include realizations with trapped ions [4-6], atomic ensembles [7], and superconducting qubits [8][9][10]. Another strategy for entanglement stabilization are measurement based protocols, which have been implemented, for example, in coupled superconducting qubits [11][12][13][14][15].The different proposed mechanisms for driven dissipative entanglement generation utilize weak resonant drivings to tailor the relaxation processes [1-10]. However, for large amplitude periodic drivings, interesting non perturbative effects are known to exist. Among these, coherent destruction of tunneling [16][17][18], Landau-Zener-Stückelberg (LZS) interferometry [19][20][21][22][23][24][25][26][27][28] and bathmediated population inversion [11,[29][30][31] have been studied in two-level systems.Relying on these later effects, we present a new mechanism to induce steady state entanglement. Using as a test system two coupled qubits, we will demonstrate that the entanglement in the steady state can be induced and tuned by changing the amplitude of a driving periodic field. One of our main results is advanced in Fig.1(a) where we show how the concurrence (a measure of entanglement) can be increased or decreased as a function of the amplitude of the periodic driving.In this work we consider two coupled qubits with HamiltonianĤ s (t) =Ĥ 0 +V (t), wherê+ with σ (i) z,x,+,− the Pauli matrices in the Hilbert space of FIG. 1. (a) Plots of the steady state concurrence, C∞, as function of the driving amplitude A/ω for 0/ω = 3 (green line) and 0/ω = 4.1 (black line). (b) Colour map of C∞ versus A/ω and 0/ω. (c) Eigenenergies Ei of the system Hamiltonian H0 as a function of 0/ω. Along this work, we choose ∆2/∆1 = 1.5 , J/∆1 = −25 and ω/∆1 = 10. The bath temperature is taken as T b /∆1 = 0.0467 and for the bath spec...

show abstract

“…Namely, the basis in which the secular approximation is carried out defines also the basis in which the dissipative transitions take place. This effect is pronounced in driven or multipartite systems, where one may, for example, choose a local approach, where the basis is chosen as the instantaneous eigenbasis of the individual constituents of the multipartite system, or the global approach, where one uses the eigenbasis of the full multipartite Hamiltonian taking into account its possible temporal trajectory [35][36][37][62][63][64][65][66]. A temporally local approach in the case of external driving has been observed to lead to unphysical results, for example, in Cooper pair pumping [67][68][69][70], and constitutes an interesting research direction.…”

Section: Introduction To the Models Usedmentioning

confidence: 99%