Multiphoton intrashell resonances in Rydberg atoms: Bloch-Siegert shifts and widths

Fregenal, D.; Horsdal-Pedersen, E; Madsen, Lars Bojer; Førre, Morten; Hansen, J. P.; Ostrovsky, V N

doi:10.1103/physreva.69.031401

Cited by 17 publications

(15 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Recently however, significant experimental effort has been put into increasing the coupling to values comparable with the Larmor frequency [2][3][4], most notable in semiconductor dots [5,6] and superconducting circuits [7][8][9][10][11][12]. Other approaches for observing the Bloch-Siegert shift include the detailed analysis of two-level Landau-Zener spectra of Rydberg atoms [13,14] and Cooper-pair boxes [15][16][17], as well as the simulation of the Rabi model in rotating frames [18,19].…”

mentioning

confidence: 99%

Observation of the Bloch-Siegert shift in a driven quantum-to-classical transition

Pietikäinen¹,

Danilin²,

Kumar³

et al. 2017

Phys. Rev. B

View full text Add to dashboard Cite

We show that the counter-rotating terms of the dispersive qubit-cavity Rabi model can produce relatively large and nonmonotonic Bloch-Siegert shifts in the cavity frequency as the system is driven through a quantum-to-classical transition. Using a weak microwave probe tone, we demonstrate experimentally this effect by monitoring the resonance frequency of a microwave cavity coupled to a transmon and driven by a microwave field with varying power. In the weakly driven regime (quantum phase), the Bloch-Siegert shift appears as a small constant frequency shift, while for strong drive (classical phase) it presents an oscillatory behaviour as a function of the number of photons in the cavity. The experimental results are in agreement with numerical simulations based on the quasienergy spectrum.The Rabi Hamiltonian -describing a two-level system coupled to a cavity (resonator) mode -is a paradigmatic model in quantum physics. In the rotating-wave approximation (RWA) it leads to the well-known JaynesCummings (JC) model. In the dispersive limit this model predicts the appearance of ac-Stark shifts in the energy levels of both the qubit and the cavity. The inclusion of counter-rotating terms produces an additional displacement of the energy levels. This Bloch-Siegert (BS) shift [1] is usually very small on standard experimental platforms since it depends on the ratio between the coupling and the sum of the Larmor and cavity frequencies. Recently however, significant experimental effort has been put into increasing the coupling to values comparable with the Larmor frequency [2-4], most notable in semiconductor dots [5,6] and superconducting circuits [7][8][9][10][11][12]. Other approaches for observing the Bloch-Siegert shift include the detailed analysis of two-level Landau-Zener spectra of Rydberg atoms [13,14] and Cooper-pair boxes [15][16][17], as well as the simulation of the Rabi model in rotating frames [18,19].In this work we take a different route. We recognize that the counter-rotating terms do not conserve the excitation number. Therefore, the natural framework for their experimental demonstration is that of driven-dissipative systems [20,21]. Guided by this intuition, we realize a setup consisting of a transmon [22] dispersively coupled to a cavity, where the cavity is driven at a fixed off-resonance microwave tone, while at the same time the spectrum is scanned by a comparatively weaker probe field, see Fig. 1. At low driving powers, we observe the expected vacuum ac-Stark shift [23][24][25][26][27]. This is followed by a transition regime dominated by nonlinear effects as the power is increased. For the Jaynes-Cummings model, such transition has been predicted and studied in the resonant qubit-cavity case [28][29][30][31]. In the dispersive limit, the transition region is no longer abrupt, but it is We drive the cavity with a detuned drive frequency ω d < ω c . The spectrum of the system is monitored by a weak probe with frequency ω p , which is swept within the window [4.36, 4.39] GHz. (d) In the T 1 measu...

show abstract

mentioning

confidence: 99%

Observation of the Bloch-Siegert shift in a driven quantum-to-classical transition

Pietikäinen¹,

Danilin²,

Kumar³

et al. 2017

Phys. Rev. B

View full text Add to dashboard Cite

show abstract

“…The effect has been observed, e.g. in pulsed ENDOR [9], circuit quantum electrodynamics systems [10][11][12], and Rydberg atoms [13].…”

Section: Introductionmentioning

confidence: 94%

Bloch-Siegert shift in a hybrid quantum register: Quantification and compensation

2018

View full text Add to dashboard Cite

Quantum registers that combine the attractive properties of different types of qubits are useful for many different applications. They also pose a number of challenges, often associated with the large differences in coupling strengths between the different types of qubits. One example is the nonresonant effect that alternating electromagnetic fields have on the transitions of qubits that are not targeted by the specific gate operation. The example being studied here is known as Bloch-Siegert shift. Unless these shifts are accounted for and, if possible, compensated, they can completely destroy the information contained in the quantum register. Here we study this effect quantitatively in the important example of the nitrogen vacancy (NV) center in diamond and demonstrate how it can be eliminated.

show abstract

“…The coupling between the two systems has an interaction strength V. Models of this kind have been considered in the literature since the early work of Bloch and Siegert [12]. Models for the energy shifts and resonance conditions for this problem have been discussed in the literature over the years (see [13][14][15][16][17]).…”

Section: Anomalous Energy Exchangementioning

confidence: 99%

Models Relevant to Excess Heat Production in Fleischmann-Pons Experiments

Hagelstein¹,

Chaudhary

2008

Low-Energy Nuclear Reactions Sourcebook

View full text Add to dashboard Cite

Observations of excess heat in the absence of commensurate energetic charged particles challenges local energy and momentum conservation, a foundation of nuclear physics. We have explored models based on excitation transfer, in which global energy is conserved but local energy conservation is violated. We present recent results on both excitation transfer and anomalous energy exchange within the context of lossless spin-boson models. We introduce a rotation that allows us to isolate terms in the rotated Hamiltonian responsible for both processes. Spin-boson type models augmented with loss appear to be sufficiently strong to account for the excess heat effect.

show abstract

Multiphoton intrashell resonances in Rydberg atoms: Bloch-Siegert shifts and widths

Cited by 17 publications

References 43 publications

Observation of the Bloch-Siegert shift in a driven quantum-to-classical transition

Observation of the Bloch-Siegert shift in a driven quantum-to-classical transition

Bloch-Siegert shift in a hybrid quantum register: Quantification and compensation

Models Relevant to Excess Heat Production in Fleischmann-Pons Experiments

Contact Info

Product

Resources

About