YBa2Cu3O7 microwave resonators for strong collective coupling with spin ensembles
Abstract
Coplanar microwave resonators made of 330 nm-thick superconducting YBa2Cu3O7 have been realized and characterized in a wide temperature (T, 2–100 K) and magnetic field (B, 0–7 T) range. The quality factor (QL) exceeds 104 below 55 K and it slightly decreases for increasing fields, remaining 90% of QL(B=0) for B = 7 T and T = 2 K. These features allow the coherent coupling of resonant photons with a spin ensemble at finite temperature and magnetic field. To demonstrate this, collective strong coupling was achieved by using di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium organic radical placed at the magnetic antinode of the fundamental mode: the in-plane magnetic field is used to tune the spin frequency gap splitting across the single-mode cavity resonance at 7.75 GHz, where clear anticrossings are observed with a splitting as large as ∼82 MHz at T = 2 K. The spin-cavity collective coupling rate is shown to scale as the square root of the number of active spins in the ensemble.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- May 04, 2015
- Source ID
- 10.1063/1.4920930
Entities
People
- A. Cassinese
- A. Ghirri
- Claudio Bonizzoni
- D. Gerace
- M. Affronte
- S. Sanna
Organizations
- Air Force Office of Scientific Research
- Istituto Nanoscienze
- Ministry of Education, Universities and Research
- University of Modena and Reggio Emilia
- University of Naples Federico II
- University of Pavia