Leading Scientist

Field of scientific interests

Quantum memory, Rare-earth-ion-doped crystals, Photon echo, Optical superradiance and subradiance, Single-photon and biphoton sources, Spontaneous parametric down-conversion, Spontaneous four-wave mixing, Microring resonators

Main scientific achievements

In the field of quantum storage:  Schemes for coherent manipulation of collective atomic states were developed such that superradiant states of the atomic system can be converted into subradiant ones and vice versa (2006). It was shown that such schemes may be used in optical quantum memory devices for storage and recall of single-photon wave packets. Optimal conditions for functioning of these devices were determined (2007). The method of storage and retrieval of single-photon wave packets in resonant media with controlled refractive index was developed (2011). Continuous change of the propagation direction of a classical control field in the process of its off-resonant Raman interaction with a weak signal field in a three-level atomic medium was suggested for quantum storage of a single-photon wave packet (2012-2013). Isotopically purified crystals YLiF doped by Nd-143 and Er-167 ions were suggested and studied for quantum memory applications (2014-2018), which includes studying them at ultralow temperatures (below 1 K), identifying optical clock and spin ZEFOZ transitions, and observation of superhyperfine splitting of energy levels via EIT. 

In the field of quantum light sources: Pulse shaping in a narrowband single-photon source based on cavity-enhanced spontaneous parametric down-conversion was analyzed. The scheme for pulse shaping was developed such that the wave form (both amplitude and phase) of heralded photons can be fully controlled by that of the pump pulse (2008). The theory of third-order spontaneous parametric down-conversion (TOSPDC) in a ring waveguide microcavity was developed (2016).  The optimal design for an on-chip single-photon source based on spontaneous four-wave mixing in a system of coupled ring microresonators, which provides the frequency-uncorrelated joint spectral amplitude of the biphoton field and thereby the generation of pure single-photon heralded states, was developed (2018). A scheme for heralded generation of frequency-bin photonic qubits via spontaneous four-wave mixing in a system of coupled microring resonators (a photonic molecule) was developed so that the qubit state is fully controlled by the frequency amplitude of the pump field (2020).       

Selected Publications

1. A.A. Shukhin, J. Keloth, K. Hakuta, A.A. Kalachev. Heralded single-photon and correlated-photon-pair generation via spontaneous four-wave mixing in tapered optical fibers. – Physical Review A, 101, 053822 (2020)
2. X. Zhang, W.-T. Liao, A. Kalachev, R. Shakhmuratov, M. Scully, O. Kocharovskaya. Nuclear quantum memory and time sequencing of a single γ-photon. – Physical Review Letters, 123, 250504 (2019)
   
3. I.N. Chuprina, A.A. Kalachev. Generating frequency-bin qubits via spontaneous four-wave mixing in a photonic molecule. – Phys. Rev. A, 100, 043843 (2019)
   
4. R. Akhmedzhanov, L. Gushchin, N. Nizov, V. Nizov, D. Sobgayda, I. Zelensky, A. Kalachev. Electromagnetically induced transparency in an isotopically purified Nd3+: YLiF4 crystal. – Phys. Rev. B, 97, 245123 (2018)
   
5. N. Kukharchyk, D. Sholokhov, O. Morozov, S.L. Korableva, A.A. Kalachev, P.A. Bushev. Optical coherence of 166Er:7LiYF4 crystal below 1 K. – New Journal of Physics, 20, 023044 (2018)   
   
6. D.A. Kalashnikov, E.V. Melik-Gaykazyan, A.A. Kalachev, Y. F. Yu, A.I. Kuznetsov, L.A. Krivitsky. Quantum interference in the presence of a resonant medium. – Scientific Reports, 7, 11444 (2017)
   
7. R.A. Akhmedzhanov, L.A. Gushchin, A.A. Kalachev, S.L. Korableva, D.A. Sobgayda, I.V. Zelensky. Atomic frequency comb memory in an isotopically pure 143Nd3+:Y7LiF4 crystal. – Laser Physics Letters, 13, 015202 (2016)
   
8. A. Kalachev, O. Kocharovskaya. Multimode cavity-assisted quantum storage via continuous phase-matching control. – Phys. Rev. A, 88, 033846 (2013)
   
9. X. Zhang, A. Kalachev, O. Kocharovskaya. Quantum storage based on control-field angular scanning. – Phys. Rev. A, 87, 013811 (2013)
   
10. A.A.Kalachev, O.A.Kocharovskaya. Quantum storage via refractive-index control. – Phys. Rev. A, 83, 053849 (2011)
    
11. A.Kalachev. Pulse shaping during cavity-enhanced spontaneous parametric down-conversion – Phys. Rev. A, 81, 043809 (2010)
    
12. A.Walther, A.Amari, S.Kröll, and A.Kalachev. Experimental superradiance and slow-light effects for quantum memories. – Phys. Rev. A, 80, 012317 (2009)    
    
13. A.Kalachev. Quantum storage on subradiant states in an extended atomic ensemble. – Phys. Rev. A, 76, 043812 (2007)
    
14. A.Kalachev, and S.Kroll. Coherent control of collective spontaneous emission in an extended atomic ensemble and quantum storage. – Phys. Rev. A, 74, 023814 (2006) 
    
15. A.A.Kalachev, V.V.Samartsev. Optical superradiance in doped crystals and its possible applications. – Laser Physics, 12, 1114 (2002)
    
16. A.A.Kalachev, L.A.Nefediev, V.A.Zuikov, V.V.Samartsev. Locking of long-lived photon echo in the presence of an inhomogeneous electric field. – Optics and Spectroscopy, 84, 811 (1998) (in Russian)