Physics / advanced
Macroscopic quantum coherence
Connect phenomenology and microscopic pairing to superconducting electrodynamics, vortices, junctions, and neutral superfluid behavior.
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Module 01 advanced
Macroscopic quantum coherence
Connect phenomenology and microscopic pairing to superconducting electrodynamics, vortices, junctions, and neutral superfluid behavior.
- 01
Magnetic screening requires more than perfect conductivity
Derive the London penetration profile and distinguish equilibrium flux expulsion from frozen magnetic history.
28 min - 02
An order parameter organizes amplitude, gradients, and gauge response
Minimize the local Ginzburg–Landau energy and identify physically meaningful phase combinations.
28 min - 03
Two length scales determine magnetic-interface behavior
Relate GL amplitude healing and field penetration to type-I and type-II classification within its stated domain.
28 min - 04
A Fermi surface changes the weak-attraction pairing problem
Derive the logarithmic Cooper binding scale and state exactly what the frozen-sea model establishes.
28 min - 05
A collective pairing state generates a self-consistent gap
Track the weak-coupling BCS gap, transition scale, and density-of-states convention.
28 min - 06
A quasiparticle mixes particle and hole amplitudes
Diagonalize one BdG block and distinguish coherence weights, electron occupations, and thermal excitation probabilities.
28 min - 07
Phase winding quantizes a fluxoid before it quantizes flux alone
Derive the charged circulation condition and connect vortex cores, magnetic halos, and vortex density.
28 min - 08
A gauge-invariant phase difference carries current through a weak link
Connect dc and ac Josephson relations to the interference of two junctions in a low-inductance SQUID.
28 min - 09
Phase rigidity and an energetic velocity threshold answer different questions
Relate neutral superflow to phase gradients and state the limits of the Landau criterion and finite-temperature order.
28 min - 10
Gap magnitude and gap sign require different experimental tests
Use nodal thermodynamics and phase-sensitive interference as complementary evidence for pairing structure.
28 min