# Resonant absorption by two-level systems


## [Jackle - 1972](https://knowen-production.s3.amazonaws.com/uploads/attachment/file/5378/10.1007_BF01401204.pdf)
⏎
## 1982 [Interaction of two-level systems with phonons. Application to the theory of glasses - S. V. Maleev](http://www.jetp.ras.ru/cgi-bin/dn/e_057_01_0149.pdf)

## Galperin

[private link - MT](https://knowen.org/nodes/27643)

## tutorials

https://wp.optics.arizona.edu/opti511r/wp-content/uploads/sites/23/2016/01/HW9_2016.pdf

https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-974-fundamentals-of-photonics-quantum-electronics-spring-2006/lecture-notes/chapter6.pdf

- thermodynamics

http://home.thep.lu.se/~larsg/Site/SM2.pdf

# Parents

* QSNS universality - Leggett et al