[RpL 1142] Re: еженедельные научные семинары

[Anna Kardakova]

Уважаемые коллеги,

На этой неделе научный семинар состоится в четверг, 6 декабря 2018, 17:00


Докладчик - Владимир Краснов (Department of Physics, Stockholm University, AlbaNova University Center, SE-10691 Stockholm, Sweden )

*Boson emission from high-temperature superconductors*

Mesastructures made of Bi2Sr2CaCu2O8+δ high-temperature superconductor 
represent stacks of atomic scale intrinsic Josephson junctions. When 
voltage is applied to such mesas, they can generate various types of 
waves (photons, phonons, polaritons, magnons, plasmons) in a variety of 
different ways. In this talk I will overview both Josephson and 
non-Josephson mechanisms of emission, including the standard 
ac-Josephson effect for emission of electromagnetic waves [1], 
segnetoelectric effect for emission of phonons and polaritons [2] and 
non-equilibrium quasiparticle relaxation and recombination for emission 
of any type of bosons, having strong electron-boson interaction and 
participating in pairing [3]. Those effects are important both for 
applied research, e.g., creation of tunable, compact, continuous wave 
and monochromatic THz source with a frequency span in the whole THz gap 
region and beyond 0.1-15 THz [1,2], and for fundamental understanding of 
the mechanism of pairing in high-temperature superconductors [3].

1. E. A. Borodianskyi and V.M. Krasnov, Josephson emission with 
frequency span 1–11 THz from small Bi2Sr2CaCu2O8+δmesa structures, 
Nature Commun. *8*, 1742 (2017).

2. S. O. Katterwe, H. Motzkau, A. Rydh, and V. M. Krasnov, Coherent 
generation of phonon-polaritons in Bi2Sr2CaCu2O8+x intrinsic Josephson 
junctions, Phys. Rev. B *83*, 100510(R) (2011).

3. V.M. Krasnov, S.O. Katterwe, & A. Rydh, Signatures of the electronic 
nature of pairing in high-Tc superconductors obtained by non-equilibrium 
boson spectroscopy. Nature Commun. *4*, 2970 (2013).


Приглашаются все желающие,

С уважением,
Анна Кардакова