Welcome to our group...

Thank you for visiting our webpage. We are the condensed matter physics group in the Department of Physics at Indian Institute of Technology Tirupati (IITT), working mainly on the strongly correlated electron system (magnetism and superconductivity), one of the most diverse fields of research in recent days.

Research interests

We are interested in the following topics:

• strongly correlated electron phenomena, e.g., spin-orbit coupled iridates, triangular and kagome spin-liquid, Mott metal-insulator transition, superconductivity and magnetism by performing experiments at extreme conditions like very low temperatures, high magnetic fields and high pressures.

• Theoretical modelling: First-principles density functional theory (DFT) for electronic band structure calculations.

Selected publications

1. Pressure-driven transitions in La₂CoTiO₆: antiferromagnetic insulator to nonmagnetic metal via antiferromagnetic metal in a double perovskite oxide, S. Nandi, S. Pradhan, A. K. Nandy, and R. S. Manna, Phys. Rev. B 110, 085101 (2024).

2. Pressure-induced dimerization and collapse of antiferromagnetism in the Kitaev material α-Li₂IrO₃, B. Shen, F. Breitner, D. Prishchenko, R. S. Manna, A. Jesche, M. L. Seidler, P. Gegenwart, and A. A. Tsirlin,   Phys. Rev. B 105, 054412 (2022)     (cited 8 times).

3. Neutron diffraction evidence for local spin canting, weak Jahn-Teller distortion, and magnetic compensation in Ti_xMn_1-xCo₂O₄ spinel, P. Pramanik, D. C. Joshi, M. Reehuis, A. Hoser, J. U. Hoffmann, R. S. Manna, T. Sarkar, and S. Thota, J. Phys.: Condens. Matter 32, 245801 (2020) (cited 12 times).

4. Anomalous charge ordering in pressure-tuned iron oxide Fe₄O₅, S. V. Ovsyannikov, M. Bykov, E. Bykova, K. Glazyrin, R. S. Manna et al., Nature communications 9, 4142 (2018) (cited 32 times).

5. Pressure dependence of spin canting in ammonium metal formate antiferromagnets, E. C.*, R. S. Manna* et al., Phys. Chem. Chem. Phys. 20, 24465 (2018), *corresponding author (cited 9 times).

6. Relaxation dynamics in the one-dimensional organic charge-transfer salt δ-(EDT-TTF-CONMe₂)₂Br, J. K. H. Fischer, P. Lunkenheimer, C. Leva, S. M. Winter, M. Lang, C. Mézière, P. Batail, A. Loidl, and R. S. Manna, Phys. Rev. B  97, 235156 (2018)        (cited 4 times).

7. Breakdown of magnetic order in the pressurized Kitaev iridate β-Li₂IrO₃, M. M.$, R. S. Manna$ et al., Phys. Rev. Lett. 120, 237202 (2018) $ = equal contribution (cited 70 times).

8. Low-temperature lattice effects in the spin-liquid candidate k-(BEDT-TTF)₂Cu₂(CN)₃, R. S. Manna et al., Crystals 8, 87 (2018) (cited 17 times).

9. Breakdown of Hooke’s law of elasticity at the Mott critical endpoint in an organic conductor, E. G., M. G., R. S. Manna et al., Science Advances 2 , e1601646 (2016) (cited 70 times).

10. Lattice strain accompanying the colossal magnetoresistance effect in EuB₆, R. S. Manna et al., Phys. Rev. Lett. 113, 067202 (2014) (cited 23 times).

11. Lattice effects in the quasi-two-dimensional valence-bond-solid Mott insulator EtMe₃P[Pd(dmit)₂]₂, R. S. Manna et al., Phys. Rev. B 89, 045113 (2014) (cited 12 times).

12. High-resolution thermal expansion measurements under helium-gas pressure, R. S. Manna et al., Rev. Sci. Instrum. 83, 085111 (2012) (cited 25 times).

13. Lattice effects and entropy release at the low-temperature phase transition in the spin-liquid candidate κ-(ET)₂Cu₂(CN)₃, R. S. Manna et al., Phys. Rev. Lett. 104, 016403 (2010) (cited 135 times).

14. Magnetic properties of CoFe₂O₄ synthesized by solid state, citrate precursor and polymerized complex methods: a comparative study, P. V., R. S. Manna, D. Banerjee, M. R. Varma, K. G. Suresh, and A. K. Nigam, J. Alloys Compd. 453, 298 (2008) (cited 181 times).