On pulse-induced transition amplitudes in a two-state quantum system without level crossings
نویسنده
چکیده
An exact dynamical parametrization of pulse-induced transition amplitudes in a Rosen–Zeneror Nikitin-type two-level system is constructed. The three dynamical parameters are closely related to the shape of the interaction pulse and are convenient to calculate. The Milne equation with a complex coefficient function is essential for these calculations. Its complex solution is non-oscillatory and makes the computation of transition probabilities efficient. The paper reviews the quantum calculations for the rectangular pulse, which has well-defined duration and strength. By comparing transition matrix elements from a rectangular pulse with those of a general symmetric pulse, we introduce effective strength and effective duration for a general pulse. It is also possible to define an equivalent rectangular pulse, with respect to the transition probabilities, for each general pulse. PACS numbers: 03.65.−w, 03.65.−Sq, 03.65.Nk, 31.15.−p, 31.15.Gy, 31.70.Hq, 32.80.Qk, 34.10.+x
منابع مشابه
Bias-Induced Optical Absorption of Current Carrying Two-Orbital Quantum Dot with Strong Electron-Phonon Interaction (Polaron Regime)
The one photon absorption (OPA) cross section of a current carrying two-orbital quantum dot (QD) with strong electron-phonon interaction (polaron regime) is considered. Using the self-consistent non-equilibrium Hartree-Fock (HF) approximation, we determine the dependence of OPA cross section on the applied bias voltage, the strength of effective electron-electron interaction, and level spacing ...
متن کاملمقدمهای بر سیستمهای اسپینی کوانتمی
This manuscript is the collection of lectures given in the summer school on strongly correlated electron systems held at Isfahan university of technology, June 2007. A short overview on quantum magnetism and spin systems is presented. The numerical exact diagonalization (Lanczos) alghorithm is explained in a pedagogical ground. This is a method to get some ground state properties on finite clus...
متن کاملUltrafast Nonlinear Optical Signals Viewed from the Molecule’s Perspective: Kramers-Heisenberg Transition-Amplitudes versus Susceptibilities
Coherent nonlinear optical signals are commonly calculated using a semiclassical approach that assumes a quantum system interacting with classical fields. Compact expressions for the signals are then derived in terms of nonlinear susceptibilities. We present an alternative approach based on a quantum description of bothmatter and field. The signals are further recast in termsof transition ampli...
متن کاملدرهمتنیدگی کوانتومی و گذار فاز کوانتومی تحت اتلاف در مدل ناهمسانگرد هایزنبرگ XXZ با برهم‌کنش ژیالوسینکی - موریا
Because the key issue in quantum information and quantum computing is entanglement, the investigation of the effects of environment, as a source of quantum dissipation, and interaction between environment and system on entanglement and quantum phase transition is important. In this paper, we consider two-qubit system in the anisotropic Heisenberg XXZ model with the Dzyaloshinskii-moriya inter...
متن کاملطراحی سوئیچ تمام نوری با استفاده از خاصیت غیر خطی Kerr وDIT با نانو کریستال چهار ترازه
We propose a novel two state and all-optical controllable switch using DIT, Kerr effect and interaction between quantum dots (QD) and quantum electrodynamics cavity (CQED). The two state and all-optical controllable switch is coupled to photonic waveguide from a rapid nonlinear environment (photonic crystal) and CQED. We consider the nano-crystal are doped to crystal photonic cavity as a 4-leve...
متن کامل