AGH University of Science and Technology, al. A. Mickiewicza 30, 30-059 Cracow, Poland.
J Phys Condens Matter. 2023 Jun 1;35(35). doi: 10.1088/1361-648X/acd7bb.
We use Floquet theory to study the effects of laser light coupling to an electron-hole pair confined in a quantum wire. Fast oscillating electric field directed along the wire continuously displaces spatially the electron and hole in opposite directions, that influences on effective time-averaged electrostatic interaction by shallowing its minimum. Renormalization of binding energy leaves distinctive stamp in Floquet energy spectra because both the ponderomotive and confining energies may be neglected in considered perturbative regime. Due to renormalization of binding energy the blueshifted dressed exciton's energy states form crossings and avoided crossings in energy spectra while their oscillator strengths are gradually reduced for increasing laser intensity, these features are strongly dependent on spatial sizes of wire. Discussed properties of Floquet exciton confined in QWr could potentially be used to build the fast terahertz optical bright-dark state switcher or to realize Floquet-Landau-Zener transition.
我们利用 Floquet 理论研究了激光与束缚在量子线中的电子-空穴对的耦合效。沿导线方向快速振荡的电场连续地将电子和空穴沿相反方向在空间上位移，这通过使其最小值变浅来影响有效时间平均静电相互作用。束缚能的重整化在 Floquet 能谱中留下了独特的印记，因为在考虑的微扰范围内可以忽略动电力和约束能。由于束缚能的重整化，蓝移的 dressed exciton 的能级在能谱中形成交叉和避免交叉，而它们的振子强度随着激光强度的增加逐渐减小，这些特征强烈依赖于线的空间尺寸。在 QWr 中受限的 Floquet exciton 的讨论性质可能被用于构建快速太赫兹光亮暗态开关或实现 Floquet-Landau-Zener 跃迁。
