Physics / advanced
Noise, decoherence, and quantum environments
Derive reduced quantum dynamics and compare unitary, Markovian, and memory-dependent descriptions without confusing decoherence with a complete measurement interpretation.
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Module 01 advanced
Noise, decoherence, and quantum environments
Derive reduced quantum dynamics and compare unitary, Markovian, and memory-dependent descriptions without confusing decoherence with a complete measurement interpretation.
- 01
System–environment entanglement and decoherence
Derive local coherence loss from environmental distinguishability while keeping the joint evolution unitary.
34 min - 02
Kraus operators and complete positivity
Build channels from unitary dilations and test trace preservation separately from complete positivity.
34 min - 03
Born, Markov, and secular approximations
Separate weak coupling, bath memory, and frequency resolution in a controlled master-equation derivation.
34 min - 04
The structure of a GKSL master equation
Connect infinitesimal channel normalization to the Lindblad generator and nonnegative dissipative rates.
34 min - 05
Amplitude damping and energy relaxation
Compute decay channels, distinguish population and coherence rates, and impose thermal detailed balance.
34 min - 06
Pure dephasing and coherence times
Separate longitudinal relaxation, transverse decay, and reversible static phase spread.
34 min - 07
Quantum regression and two-time correlators
Propagate operator-weighted states and identify the extra assumptions behind a regression formula.
34 min - 08
Quantum trajectories and unravelings
Connect conditional environment records to jump updates while recovering the unconditional master equation.
34 min - 09
Non-Markovian memory kernels
Use an exact finite-environment model to separate valid initial-time channels, divisibility, and information revival.
34 min - 10
Environment engineering and dissipative steady states
Design a target state using jump operators, then test uniqueness, convergence, and competing noise.
34 min