Cavity QED is the study of quantum effects on small cavities, manifested in variations in the lifetimes of unstable energy levels

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Photon in the box electric field strength

If we put a photon in a box and suppose the resonant frequency is $f$. If we know the volume $V$, How do we approximate the electric fields at the center of the box?
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Change in Q factor on tuning external magnetic field in Electron spin resonance experiment

Does the Q factor of the cavity resonator show a dip at the resonant value of the external magnetic field while performing an ESR experiment?If so, what is the physical reason behind it?
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Simulating TE011 mode in cylindrical cavity, Comsol [closed]

I have been trying to simulate TE011 mode in a cylindrical cavity by modifying the example given in Comsol site(https://www.comsol.co.in/model/computing-q-factors-and-resonant-frequencies-of-cavity-...
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Role of Cavity Resonators in continuous wavelength-electron paramagnetic resonance(CW-EPR)

Why is it necessary to place the sample in a cavity resonator for obtaining EPR spectrum in CW-EPR? What role does a cavity resonator play in a CW-EPR spectrometer?
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71 views

QED+Classical Background Renormalization

I would like to ask a question related to quantum corrections and renormalization in QED. We have the QED vertex $\overline{\psi}[-ie \gamma^{\mu}(B_{\mu}+A_{\mu})]\psi,$ being $B_{\mu}$ a classical ...
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60 views

How to experimentally create an atom in a superposition of ground and excited states? [closed]

For Quantum Computing we use atoms in superposed states, but how do we physically create them?
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111 views

How does the electric field operator change inside an optical cavity

In the free field, transverse electric field operator is given by the below expression; $$d^{\bot}(R)=i \sum_{p,\lambda}\Big( \frac{\hbar cq}{2V\epsilon_{0}}\Big)^{1/2} \{e^{(\lambda)}(p)a^{(\lambda)}...
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1answer
90 views

Why is the frequency bandwidth of the environment important for Markovianity?

In the derivation of Spontaneous Emission in two level systems in Quantum Optics (be it Wigner Weisskopf or a different approach, such as density operators to find the master equation), one makes (...
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467 views

Collapse and revival in the Jaynes Cummings model

I'm having some trouble understanding the exact details of the collapse and revival in the Jaynes Cummings model. What I understand is this: We assume our two level atom to initially be in the ...
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1answer
95 views

Introducing time-dependent drive into the Hamiltonian of quantised electric circuits

Suppose I have the schematic of a superconducting electric circuit composed of (quasi) lossless linear inductances and capacitances and some non-linear inductances, eg. Josephson junctions. The ...
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1answer
96 views

Commutation of field and atomic ladder operators in the Dicke model

Consider the Dicke model, whose Hamiltonian is (in the rotating wave approximation) \begin{equation} \hat H=\omega_c \hat a^\dagger \hat a+\omega_0 \hat \sigma_z + g(\hat a^\dagger \hat \sigma + \hat ...
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63 views

Why is the limit to observe quantum phenomena $k_B T < \hbar \omega_0$ in cavity QED?

In cavity QED you have to cool down the appartus so that quantum effects may be observed in a way that $k_B T << \hbar \omega_0$. I suppose that $\omega_0$ here means the frequency which the ...
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spread of fock state distribution and infinite revival time of rabi oscillation in spontaneous emission

In cavity QED for a 2-level atom, the revival time for oscillation b/w the states $\left|\ e\ 0\right\rangle$ and $\left|\ g\ 1\right\rangle$ (absorbing the same photon that is emitted) is said to be ...
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What are the “strong”, “ultrastrong” and “deep strong” coupling regimes of the Rabi model?

The Rabi model describes a two-level system interacting via a linear coupling with a quantized harmonic oscillator, and it is described by the hamiltonian $$ H_{\rm{Rabi}}=\hbar\omega\, a^\dagger a +\...
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1answer
87 views

How is a qubit realized in a cavity?

Considering a single photon in a cavity, how is a qubit realized in this setup? How is the qubit $|0\rangle$ or $|1\rangle$ manipulated? I.e. how are the transitions $|0\rangle \to |1\rangle$ and $|1\...
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2answers
220 views

Partition Function for the Jaynes-Cummings Hamiltonian

I was wondering if anyone here has calculated before the partition function for the Jaynes-Cummings Hamiltonian: $H_{JC}=\omega_0 (a^\dagger a + \sigma^+ \sigma^-)+g (a \sigma^+ +a^\dagger \sigma^-)$ (...
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508 views

Strange modulation of radioactive decay rates with solar activity

Recently I found out this strange article about nuclear decay rates somehow showing seasonal variations with a high correlation with sun activity. Has this been experimentally confirmed/disproved? ...
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196 views

Does the Casimir effect allow to change the lifetime of a radiating atom?

Is it true that a spontaneously light-emitting atom changes its lifetime if it is put between two parallel plates that are so near that they attract each other through the Casimir effect? Thus: does ...