update project notes

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Valentin Boettcher 2022-05-16 17:43:13 +02:00
parent c488f423c5
commit dd22a26afa
3 changed files with 156 additions and 14 deletions

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@ -86,7 +86,7 @@ CLOCK: [2021-10-07 Thu 13:38]--[2021-10-07 Thu 17:50] => 4:12
**** DONE TeX interaction energy
**** DONE Implement interaction energy for multiple baths.
- plot it for tal
**** TODO Test it with the two-qubit model
**** DONE Test it with the two-qubit model
**** TODO Initial Slip
- [[file:calca/heat_flow/initial_slip_zero_int.xopp][see notes on zero interaction]]
- for self adj -> apparently tempertature independent
@ -94,9 +94,10 @@ CLOCK: [2021-10-07 Thu 13:38]--[2021-10-07 Thu 17:50] => 4:12
proportional to integral of imag part of BCF -> normalizing to one
is helpful: explains why ω_c has influence on coupling strength (as
seen in the new trunc scheme)
***** NEXT Adjust normalization of model
***** TODO Verify that this works
**** TODO Q-Trid -> how non-thermal?
***** DONE Adjust normalization of model
***** DONE Verify that this works
***** TODO Verify time dependent
**** HOLD Q-Trid -> how non-thermal?
**** DONE Influence ω_c on initial slip and shape
- see [[file:calca/heat_flow/initial_slip_zero_int.xopp][the notes]]
- without non-zero system: generally enhanced flow (why?)
@ -123,7 +124,8 @@ CLOCK: [2021-10-07 Thu 13:38]--[2021-10-07 Thu 17:50] => 4:12
- fit quality
- switched to fitting 2/3 where bcf is big and the rest on the tail
****** TODO Try less symmetric
****** TODO Port to new system
****** TODO Try less symmetric
*** DONE figure out why means involving the stoch. process are so bad
- maybe y is wrong -> no
@ -142,11 +144,12 @@ CLOCK: [2021-10-07 Thu 13:38]--[2021-10-07 Thu 17:50] => 4:12
- Properties
- Initial time: \(E_{\text {int }}(0):=\operatorname{Tr}\left[\rho_{\mathrm{S}}(0) H_{\mathrm{S}}\right] \quad\left(H_{\mathrm{S}}^{\circledast}(0, \beta)=H_{\mathrm{S}}\right)\)
**** DONE Find Rivas Paper
*** TODO Physical Implication Single Bath
*** HOLD Physical Implication Single Bath
- how far away from thermal state
- exponential decay for markov case?
*** TODO Think about Higher moments
*** TODO Why does the expression containing the first hier. states converging faster.
- see [[file:calca/heat_flow/higher_order.xopp][notes]]
*** HOLD Why does the expression containing the first hier. states converging faster.
** HOLD Steady State Methods
- [[file:python/energy_flow_proper/05_gaussian_two_baths/longhopsidea.org][cholesky transform]] seems to provide us with the posibility of
generating tree like processes
@ -165,7 +168,7 @@ CLOCK: [2021-10-07 Thu 13:38]--[2021-10-07 Thu 17:50] => 4:12
- negative thermal conductance at low coupling strenght between
qubit and mode
- thermal transistor with two qubits and one mode
*** TODO Two Qubits
*** HOLD Two Qubits
**** NEXT Hamiltonian
- [[file:calca/qubit_model/general_model.xopp][see notes]]
- look at cite:Kato2015Aug
@ -223,7 +226,7 @@ CLOCK: [2021-10-07 Thu 13:38]--[2021-10-07 Thu 17:50] => 4:12
- cite:Aurell2019Apr -> jump processes, one bath
- effective description
- rate/kinetic equations
*** TODO Three Bath Fridge
*** HOLD Three Bath Fridge
here is the paper I had in mind when we talked about the three-bath fridge.
@ -238,9 +241,146 @@ This fridge is working continuously. Maybe for HOPS a stroke-based model could b
https://link.springer.com/article/10.1140%2Fepjs%2Fs11734-021-00094-0
- cite:Karimi2016Nov -> one HO and two resonators
*** TODO Realistic Models
- cite:Mu2017Dec, cite:Binder2018 -> linear additive coupling can't be used to attain cooling
*** HOLD Realistic Models
- ask Kimmo about quantum dots
- look at prof. strunzs paper again
*** TODO Heat Engines
See cite:Binder2018.
- our strengths lie in medium/fast non-periodic driving
- carnot maybe good idea: expansion and coupling at the same time
- we need at least two baths -> non passive
- stronger coupling + coherence should decrease
- interesting effects if H(t) does not commute for different times
- adiabaticity still present even with stronger coupling?
- monotonic convergence to steady state is guaranteed cite:Feldmann2004Oct
- distance measure is the relative entropy: not symmetric
- shortcut to adiabaticity -> performance boost
**** TODO Ref 92
- convergence to limit cycle only for weak?
- I don't think so
**** TODO Look at 105
**** TODO Chapter Two: How applicable to our case?
**** DONE Single Bath Time Dependence
- no energy extraction due to passivity
- WRONG!, indeed you can, but it's likely bounded
- N - times the same HO definitely is, see [[file:python/energy_flow_proper/ergo_stuff/ergotropy_bath_qubit.org][my ergotropy experiments]] and [[file:calca/qubit_model/passive_states_once_more.xopp][calculations]]
- small but finite changes let things blow up. i suspect this was a waste of time
- see also [[file:calca/heat_flow/initial_slip_zero_int.xopp][my notes on pure dephasing]] -> no energy transfer dephasing at all
- see [[file:python/energy_flow_proper/08_dynamic_one_bath/coupling_modulation.org][modulation experiments]] and cite:Binder2018
- as far away from dephasing as is possible
**** TODO Connection to Prior Art
- find out how much theorems are violated
- are there STIRUP-like surprises: overlapping and swapping stages
***** TODO Find results to reproduce
- strong coupling with HO WM: cite:Wiedmann2021Jun
- stirling: non-markovian cite:Raja2021Mar
- strokes separate, no overlap
- apparently higher eff than quasistat -> but only without thermalization
- only qubits
- second order in coupling -> born approx, no bath change cite:Kofman2004Sep
- carnot-like: cite:Scopa2018Jun uses GKSL-Floquet
****** (old) spin-1/2 in weak-coupling: cite:Geva1992Feb
- refers to laser with semigroup model: Curzon-Ahlborn efficiency (in classical limit)
- speaks of endoreversibility
- irreverisibility through coupling
- this work: more easily compared with classical, b.c. no simultaneous heat contact
- qubit: no classical analog, simple
- questions: curzon-ahlborn still valid, approaching equilibrium
limit?, effect of quantum mechanics per-se
******* Model
- **many** non interacting spins as working fluid (multiply everything by N)
- **does this make a difference?**
- carnot cycle: two isothermal br., two adiabatic
- modulation has no zero, simpliy magnitude of magnetic field, commutes with \(H\)
- effecive diagonality
******* Work, Heat, Temp
- power and heat naively defined by instantaneous limits
#+DOWNLOADED: screenshot @ 2022-05-09 15:22:34
[[file:Tasks/2022-05-09_15-22-34_screenshot.png]]
#+DOWNLOADED: screenshot @ 2022-05-09 15:22:54
[[file:Tasks/2022-05-09_15-22-54_screenshot.png]]
- cite:Binder2018 says this is problematic outside the limit cycle if
modulation is fast: work vs. internal energy (do we have this problem?)
- Modulating H does not change population
- negative Temperatures as artifact of non-positive
******* Cycles
- temperature equilibration is performed
- sudden limit: otto cycle efficiency upper bound for all
- step cycle converges onto reversible
- final cycle: detailed balance for the gksl -> time dependent coefficients (but ok if slow-varying)
otherwise problematic
- non-equilibrium -> "temperatures of the working fluid not the same as the baths"
******* Striking Findings
- different heat transfer law
- high temperature limit:
- times for isothermal branches
- at maximum power: times independent of the isotherm temperatures
- explicit modulation
- maximum power at curzon-ahlborn eff, effectiveness 1/2
- similar to newton but need not be close to eq.
****** General Notions in cite:Kurizki2021Dec
- continous
******* Reciprocating Engines
- adiabatic limit: wm state diagonal, efficiency 1-ω_c/ω_h
- coherence generated when hamiltonian (system driving) does not
commute with itself: extra (external) work
- making the state non-passive is costing work
- in sudden limit: cohorence gives work extraciton, *markov*
- non-passivity for unitary extraction from the work medium
- all engine types are equivalent (map over one cycle) when action small cite:Uzdin2015Sep
- equivalence of map, but not state inside cycle
- thermodynamic heat/power also converge to same
- continous engines only extrac work from coherences
******* TODO 18, 22 -> ergotropy
- tighter bound p. 268 for entropy change
- 18: nonthermal baths are special and may perform work
- 22: nonpassivity of piston states -> work
- maybe later: *implement machine proposed in HOPS*
***** TODO Find Theorems to break
- quantum speed limit
- quantum friction
- stochastic cycles: efficiency limit cite:Binder2018
- symmetry of expansion and compression
- modulating the nature of the coupling may be interesting
- fast driving + overlap of strokes
- level of non-adiabaticity
- how much is spohn violated
- ergotropy production
- dependence on cutoff
- limit-cycle: constant energy and entropy? (probably)
- fast modulation: more complicated "einschwingen", energy exchange
with external source not to be neglected
- sudden limit->finite work? and adiabatic limit.
(maybe even easier to define with finite memory)
- reversibility? how to define?
- *sudden limit*: equivalence of continous and stroke broken with a lot of memory?
- may need big actions
- detect signatures from cite:Uzdin2015Sep
- *continous engines*: coherences are only source of work
- defines a classical engine
- cite:Kurizki2021Dec: p. 268 -> heat and entropy inequalities may be
broken, gives concrete conditions
***** TODO Model Ideas
- for starters: qubit
- two coupled qubits also nice
- non-scalar time dependence
- period of high int-strength followed by period of low for thermalization
- maybe extra dephasing step -> should remove power output
- notion of instantaneous temperature? cite:Geva1992Feb
- continous cycle machines: may have quantum advantage cite:Kurizki2021Dec
- coherence work extraction
- maybe contrast stroke vs continous?
**** NEXT Implement Two-Bath Qubit
** DONE Talk
*** DONE Plan
**** RESOLVED How much introduction
@ -257,11 +397,12 @@ https://link.springer.com/article/10.1140%2Fepjs%2Fs11734-021-00094-0
- intesting: anti-herm part is probability decay
- decay is stronger the higher the depth
**** DONE TeX it
**** TODO Truncation scheme
**** HOLD Truncation scheme
- what does it mean if the norms are small?
- apparently with coupling it still works
- maybe dynamic truncation
**** TODO TeX It
**** DONE TeX It
*** TODO Hopsflow Power
** Quantum Thermo
*** How is heat flow measured?
- cite:Stevens2021Sep energy change in qubit drive field conditioned on measurement outcome
@ -301,7 +442,7 @@ https://link.springer.com/article/10.1140%2Fepjs%2Fs11734-021-00094-0
*** Thermal Operations
** Entropy Dynamics
** Effective thermal states (forget coherences)
*** ASK what is eigenstate thermalization
*** DONE what is eigenstate thermalization
*** Preferred Basis
** Automatic definition of interaction so that interaction energy stays zero
@ -317,9 +458,10 @@ https://link.springer.com/article/10.1140%2Fepjs%2Fs11734-021-00094-0
** cite:Esposito2015Dec exclude definitions because not exact differential
** What happens to the interaction H in steady state
** Why does everything come to a halt except the bath?
** ASK General Coupling Operators?
* Questions
** RESOLVED what is a kinetic equation
** ASK what is feschbach projection
** DONE what is feschbach projection
** DONE Look up Michele Campisi
- identify heat source first: then definition :)
- entropy production positive not quite second law: not thermodynamic entropy