Questions tagged [open-quantum-systems]
The study of open quantum systems is concerned with understanding and predicting the dynamics of quantum systems that are coupled significantly to their surroundings, leading to effects such as dissipation and decoherence.
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Question about self-orthogonality of non-Hermitian Hamiltonians
This is my second attempt at this question, the first one got deleted because my question was lacking detail. My knowledge of this subject comes entirely from these two sources: Nimrod Moisyevitch, ...
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The physical meaning of the "coupling operator"
I am reading Vassili N. Kolokoltsov's paper arXiv:2505.14605, "On the Mathematical Theory of Quantum Stochastic Filtering Equations for Mixed States", and having trouble understanding the ...
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"Hopping" in tight binding versus "hopping" transport in disordered system
People use the same word "hopping" for tight-binding off diagonal matrix element as well as incoherent electron transport in disordered/localized system. I feel like those are totally ...
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When is the post-jump state in the Lindblad equation pure, and when is it mixed?
In the Lindblad master equation,
\begin{equation}
\frac{d\rho}{dt} = -i[H, \rho] + \sum_k \left( L_k \rho L_k^\dagger - \tfrac{1}{2}\{ L_k^\dagger L_k, \rho \} \right),
\end{equation}
the dynamics ...
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How does one go from the short-time stochastic evolution of a single quantum trajectory to the ensemble master equation?
In the quantum-jump (Monte Carlo) method described in Quantum Optics by Gerry and Knight, consider a single-mode cavity field where photons are lost at rate $\gamma$. For a single trajectory $|\Psi\...
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Lindblad operators in a composite system
Consider a qubit described by a Hilbert space with basis vectors $|0\rangle$ and $|1\rangle$. The system undergoes spontaneous decay, modeled by a master equation in Lindblad form with a Lindblad ...
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On the assumptions of spontaneous emission in two-level atomic system
I was following lecture notes on light-matter interactions by Claudiu Genes (pdf link). Refer to chapter 1 : we are dealing with a two level atomic system governed by the ladder operators $\sigma = |g\...
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Is the Lindbladian evolution invertible?
In the context of the Lindblad equation and finte dimensional systems:
$$\partial_t \rho(t) = \mathcal{L}(t)\rho(t)$$
we can introduce a evolution superoperator $\mathcal{E}(t,t_0)$ that fulfills the ...
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Solving the Schrodinger equation in the single excitation manifold
I have been trying to solve the Schrodinger equation for a TLS weakly coupled to the EM field along with a 'semi-classical' atom-drive term, with the TLS initially in ground and the field initially in ...
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I need help to understand strong symmetry Lindbad equation
I am in the process of constructing a Lindbad equation within strong symmetry regime for a two-level two qubit system.
$$
\dot\rho \;=\; -\frac{i}{\hbar}[H,\rho]
\;+\;\gamma\,\mathcal D_{\rm coll}[\...
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Quantum trajectories for Lindblad systems: non-linear quantities
When computing averages using the method of quantum trajectories, can one estimate quantities that are nonlinear in the density matrix, such as the purity, by replacing it with the sample average:
$$
\...
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How to construct the jump operator in the Lindblad master equation for a 4-level atomic system?
The atomic system I am considering has the four following energy levels.
The lowest energy level, labeled $| 1 \rangle $, corresponds to the ground state $6S_{1/2}$. From this state, the atoms are ...
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How to define Lindblad jump operators for gain and loss in the SSH model?
Consider SSH model with gain and loss at the boundaries (Imaginary On-site potential), and I want to understand how to define the corresponding Lindblad jump operators in this system.
There are two ...
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Purity of continously measured open quantum system
An open quantum system can be described by the Lindblad master equation. If one wants to describe an open system, which is continously measured, one can describe such a system using a stochastic ...
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What does a typical spectral density function $J(\omega)$ look like for a solar photon bath, and internal vibrational phonon bath?
I am currently creating a simulation to simulate different systems of light absorbing molecules that are coupling to a photon bath (sun) and a phonon bath (internal vibrations). I have picked a ...
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