Direct Observation of Excitonic Rabi Oscillations in Semiconductors

Schülzgen, Axel; Binder, R.; Donovan, M.; Lindberg, M.; Wundke, K.; Gibbs, H. M.; Khitrova, G.; Peyghambarian, N.

doi:10.1103/physrevlett.82.2346

Cited by 192 publications

(121 citation statements)

References 15 publications

Supporting

Mentioning

115

Contrasting

Unclassified

Order By: Relevance

“…Many of the excitation of the electron systems can be well described by the liner response scheme, and the nonlinear interaction between light and matter is recognized as the origin of many physical processes [83]. Rabi oscillations, which occur between stationary states of systems of two-state quantum near an oscillatory driving fields and its energy transitions, are periodical.…”

Section: Rabi Oscillationsmentioning

confidence: 99%

Exciton-plasmon coupling interactions: from principle to applications

et al. 2017

View full text Add to dashboard Cite

Abstract:The interaction of exciton-plasmon coupling and the conversion of exciton-plasmon-photon have been widely investigated experimentally and theoretically. In this review, we introduce the exciton-plasmon interaction from basic principle to applications. There are two kinds of exciton-plasmon coupling, which demonstrate different optical properties. The strong exciton-plasmon coupling results in two new mixed states of light and matter separated energetically by a Rabi splitting that exhibits a characteristic anticrossing behavior of the exciton-LSP energy tuning. Compared to strong coupling, such as surface-enhanced Raman scattering, surface plasmon (SP)-enhanced absorption, enhanced fluorescence, or fluorescence quenching, there is no perturbation between wave functions; the interaction here is called the weak coupling. SP resonance (SPR) arises from the collective oscillation induced by the electromagnetic field of light and can be used for investigating the interaction between light and matter beyond the diffraction limit. The study on the interaction between SPR and exaction has drawn wide attention since its discovery not only due to its contribution in deepening and broadening the understanding of SPR but also its contribution to its application in light-emitting diodes, solar cells, low threshold laser, biomedical detection, quantum information processing, and so on.

show abstract

Section: Rabi Oscillationsmentioning

confidence: 99%

Exciton-plasmon coupling interactions: from principle to applications

et al. 2017

View full text Add to dashboard Cite

show abstract

“…1 The effect increases with electron-hole concentration. In the regime of coherent pumping at the exciton resonance, the light-field dresses the electron-hole gas and dynamical Stark splitting has been clearly observed in GaAs quantum wells embedded 2 or not 3,4 in a microcavity. Actually, in this coherent regime, the excitation-induced dephasing is found to be reduced as a result of the significant decrease of the Coulomb collision rates.…”

mentioning

confidence: 99%

Dressed excitons within an incoherent electron gas: Observation of a Mollow triplet and an Autler-Townes doublet

2008

View full text Add to dashboard Cite

We demonstrate that the interaction between excitons and a sea of incoherent electrons does not preclude excitons dressing by light. We investigate if exciton-electron scattering plays some inhibiting role in the coherent light-exciton coupling by measuring the dynamical absorption spectrum of a modulation-doped CdTe quantum well that shows clear evidence for significant electron scattering of the excitonic states. We show the occurrence of dressed and correlated excitons by detecting quantum coherent interferences through excitonic Autler-Townes doublet and ac Stark splitting that evolves into a Mollow triplet with gain. We also evidence the partial inhibition of the electron-exciton scattering by exciton-light coupling. DOI: 10.1103/PhysRevB.77.121301 PACS number͑s͒: 78.67.De, 71.35.Cc, 71.35.Ee, 78.47.Ϫp The absorption spectrum of semiconductor quantum wells is dominated by a strong exciton resonance. Excitons are bound, conduction electron valence-hole pairs and are quite often compared to a two level system as a hydrogen atom. The role of many body interactions and exciton correlations in the exciton dynamical absorption spectrum has attracted much interest for several decades. The response of the exciton absorption to an incoherent and thermalized electronhole population obtained through nonresonant pumping in the continuum corresponds mainly to a broadening of the exciton resonance that is dominated by collision broadening ͑excitation-induced dephasing͒ rather than by a bleaching due to the saturation of the oscillator strength caused by phase space filling.1 The effect increases with electron-hole concentration. In the regime of coherent pumping at the exciton resonance, the light-field dresses the electron-hole gas and dynamical Stark splitting has been clearly observed in GaAs quantum wells embedded 2 or not 3,4 in a microcavity. Actually, in this coherent regime, the excitation-induced dephasing is found to be reduced as a result of the significant decrease of the Coulomb collision rates.5 As a consequence, the light-induced exciton dressing renders this many-body excitonic system comparable to a noninteracting atom system. 6 This issue is very important if one tries to extend coherent manipulations as those performed in atomic systems 7 to semiconductors in view of possible applications. In modulation-doped semiconductor quantum wells, excess carriers coalesce with excitons to form charged excitons ͑trions͒. The absorption spectrum is then modified: a trion resonance appears below the exciton resonance.8 However, many-body interactions also tend to become more complex. Electrons, for instance, are known to strongly screen the exciton oscillator strength 8,9 and to modify their linewidth and binding energy through exchange interactions.10 Thus, the shape of the exciton line, as well as that of the trion line, depends strongly on the strength of electron scattering with excitons and trions. Indeed, we have observed, as others before us, that a high-energy tail develops at both exciton and trion res...

show abstract

“…This generic feature of Rabi oscillation is universally found in a vast variety of material systems ranging from simple atoms and molecules [6][7][8][9][10] to bulk semiconductors [11], quantum wells and dots [12][13][14][15], graphene [16], surface plasmons [17], superconducting interference devices [18,19], diamond nitrogen-vacancy centers [20], and Bose-Einstein condensates [21], etc. When a two-state atom interacts with a resonant (δ = 0) laser pulse, the dynamics of the excited state probability, which we may refer to as single-atom Rabi oscillation (SARO), is represented by…”

mentioning

confidence: 99%

Ultrafast laser-driven Rabi oscillations of a trapped atomic vapor

2015

View full text Add to dashboard Cite

We investigate Rabi oscillation of an atom ensemble in Gaussian spatial distribution. By using the ultrafast laser interaction with the cold atomic rubidium vapor spatially confined in a magnetooptical trap, the oscillatory behavior of the atom excitation is probed as a function of the laser pulse power. Theoretical model calculation predicts that the oscillation peaks of the ensemble-atom Rabi flopping fall on the simple Rabi oscillation curve of a single atom and the experimental result shows good agreement with the prediction. We also test the the three-pulse composite interaction Rx(π/2)Ry(π)Rx(π/2) to develop a robust method to achieve a higher fidelity population inversion of the atom ensemble.PACS numbers: 32.80. Qk, 32.80.Wr, 42.65.Re Rabi oscillation is a fundamental concept in physics with a significant pedigree first discovered in the context of nuclear magnetic resonance (NMR) [1][2][3] and later extended to atomic physics and quantum optics [4,5]. In the presence of an oscillatory driving field E(t) = A(t) cos(ωt), a two-state quantum system undergoes a cyclic change of Bloch vector ρ manifested by the precessionabout an effective torque Ω = (−µA(t)/2 , 0, δ), where µ is the transition dipole moment between the two energy states, A(t) is the field envelope, and δ is the frequency detuning under the slowly-varying envelope approximation [4]. This generic feature of Rabi oscillation is universally found in a vast variety of material systems ranging from simple atoms and molecules [6][7][8][9][10] When a two-state atom interacts with a resonant (δ = 0) laser pulse, the dynamics of the excited state probability, which we may refer to as single-atom Rabi oscillation (SARO), is represented bywhere Θ o is the pulse area defined by Θ o = µA(t)dt/ . Since the pulse area is subject to both the pulse duration and the electric-field envelope, Rabi oscillations of an ultra-short time scale can be implemented by ultrafast optical interaction at a strong-enough laser intensity regime. However, the spatial extent of the laser beam over the laser-atom interaction region inevitably causes spatial average effect that often leads to vanishing of the oscillatory behavior. To overcome this problem, homogenizing the spatial profile of laser beams [22,23] and * Electronic address: jwahn@kaist.ac.kr adapting chirped laser interaction [24] have been considered. This paper aims quantitative analysis of spatially averaged Rabi oscillation. For this, we use the atom ensemble localized in a magneto-optical trap (MOT) [25] interacted with ultrafast laser pulses. As a theoretical model to investigate the spatially inhomogeneous interaction, we consider a Gaussian laser beam propagating along z direction. The pulse area in Eq. (2) is then represented in the polar coordinate system aswhere r = x 2 + y 2 , w(z) is the beam waist at z, w o = w(0) is the minimal beam waist, Θ o is the maximal pulse area, and Θ z = w o Θ o /w(z). When we assume the atom density profile in the MOT is also a Gaussian, i.e., ρ(r, z) = ρ o e −(r 2 +z 2 ...

show abstract

Direct Observation of Excitonic Rabi Oscillations in Semiconductors

Cited by 192 publications

References 15 publications

Exciton-plasmon coupling interactions: from principle to applications

Exciton-plasmon coupling interactions: from principle to applications

Dressed excitons within an incoherent electron gas: Observation of a Mollow triplet and an Autler-Townes doublet

Ultrafast laser-driven Rabi oscillations of a trapped atomic vapor

Contact Info

Product

Resources

About