Dr. Hardeep Kumar received his B.Sc. degree in Non-Medical from Himachal Pradesh University, Shimla in 2002 and M.Sc. degree in Physics from Guru Nanak Dev University Amritsar in 2004. He obtained Ph.D. degree in Physics from I.I.T. Delhi in 2011. His Ph.D. work is based on magnetic granular thin films. Dr. Hardeep worked as FAPESP Post-doctoral Fellow at University of Sao Paulo, Brazil from 09/2011 to 05/2014 and joined Amity University UP, Noida as Assistant Professor in 10/2014 and worked there for about 3 Year and 7 Months. He joined NIT Uttarakhand as Assistant Professor in 06/2018. Dr. Hardeep has co-supervised one Ph.D. scholar (07/2016-03/2021), and currently two Ph.D. students are working under his sole supervision in the area of Spintronics . He completed one research project (2016-19) sponsored by UGC-DAE CSR , Indore, and currently working on a project (2020-till date) sponsored by UGC-DAE CSR , Indore. His research interests are magnetic heterostructures for spintronics ap
EDUCATION
* Ph.D. (Physics) - Indian Institute of Technology Delhi, India - 2011
* M.Sc. (Physics) - GNDU Amritsar, India - 2004
Role of spin-glass-like interfaces in exchange-biased MnN/Fe thin films grown on W buffer layers Hardepinder Singh, Mukul Gupta, Hind Prakash, Hardeep Kumar, Himanshu Fulara Applied Physics Letters, 2024 This study reports the growth and investigation of (001)-oriented MnN/Fe thin films on the W buffer layer, focusing on detailed exchange bias (EB) studies, including thermal evolution (300–10 K) and the training effect. At room temperature, the magnetically annealed α-W/MnN/Fe/Ta stack exhibits an EB field (HEB) of 118 Oe. With decreasing temperature, particularly below 100 K, both HEB and coercive field (HC) show substantial increases, with HEB displaying a more pronounced enhancement. Analysis of the temperature-dependent HEB and HC data reveals an exponential trend, indicative of a spin-glass-like interface in the MnN/Fe system. At 10 K, the pronounced EB is accompanied by an asymmetric “kinked” magnetization reversal, suggesting a transition from uniaxial to biaxial anisotropy below 50 K due to spin-glass-like magnetic frustration at the interdiffused MnN/Fe interface. Training effect measurements further support the spin-glass-like MnN/Fe interface, with two distinct training mechanisms observed at 10 K: “athermal” and “thermal.” Finally, the spin-glass model demonstrates an excellent fit for the training effect data, validating the presence of spin-glass-like disorder at the MnN/Fe interface.
Evidence of local structural influence on the shape driven magnetic anisotropy in electronically excited Ni nanoparticles embedded in SiO2 matrix Debalaya Sarker, Saswata Bhattacharya, H. Kumar, Pankaj Srivastava, Santanu Ghosh Scientific Reports, 2018 The reliance of modern electronic era on ultrafast data recording has made the search for novel tools to tune nano-scale magnetic-anisotropy (MA) never-ending. We demonstrate a strong correlation between the spin-spin interactions, local atomic structure and the MA of Ni nanoparticles (NPs) embedded inside SiO2 matrix under swift heavy ion (SHI) irradiation. In contrast to traditional understandings, MA in Ni NPs along with their aspect ratio, first increases upto 5 × 1013 ions/cm2 SHI fluence (5e13) and gets reduced at highest fluence. Using angle dependent Extented-Xray-Absorption-Fine-Structure (EXAFS) and ab initio molecular dynamics (MD) simulations, we show that the anisotropy induced in local atomic structure upon irradiation is dependent on atomic spin-spin interactions, which gets reduced at highest fluence. The chosen model cluster (Ni38) used in our MD simulations is duly validated by comparing the pair-correlation-function of the structure with the EXAFS-Fourier-Transform. The lattice temperatures for the films irradiated at different fluences, as calculated from thermal-spike-model, are used for the respective MD runs. We conclude that the enhanced disorder in both the local atomic environment and spin alignment destroys the MA at the highest fluence in SHI irradiated Ni NPs. The findings therefore provide rich conceptual insights for designing magnetic devices using SHI-induced phenomena.
Strain effects on the magnetic order of epitaxial FeRh thin films H. Kumar, D. R. Cornejo, S. L. Morelhao, S. Kycia, I. M. Montellano, N. R. Álvarez, G. Alejandro, A. Butera Journal of Applied Physics, 2018 In this work, we report the experimental results obtained on a set of ∼90 nm thick FeRh epitaxial films deposited on MgO (001), MgO (111), and Al2O3 (0001) single crystal substrates. The magnetic characterization was achieved by measuring magnetization curves and ferromagnetic resonance as a function of temperature and orientation of the films with respect to the applied magnetic field. We discuss our results by comparing the characteristics of the antiferromagnetic-ferromagnetic transition among FeRh films of the same thickness but exposed to different post-growth annealings and deposited on substrates of different crystalline orientations. We have found that there is a correlation between the strain present in the films and their magnetic behavior, observing that a change in the in-plane stress from compressive to tensile tends to shift the magnetic transition by more than 60 K. The interplay between magnetic and elastic properties was further analyzed by ferromagnetic resonance, and we have found that the magnetoelastic component of the anisotropy varies from out-of-plane to in-plane, depending on the substrate. These findings could be of great importance if a precise tuning of the magnetic transition temperature or the magnetic anisotropy is needed for a specific application.In this work, we report the experimental results obtained on a set of ∼90 nm thick FeRh epitaxial films deposited on MgO (001), MgO (111), and Al2O3 (0001) single crystal substrates. The magnetic characterization was achieved by measuring magnetization curves and ferromagnetic resonance as a function of temperature and orientation of the films with respect to the applied magnetic field. We discuss our results by comparing the characteristics of the antiferromagnetic-ferromagnetic transition among FeRh films of the same thickness but exposed to different post-growth annealings and deposited on substrates of different crystalline orientations. We have found that there is a correlation between the strain present in the films and their magnetic behavior, observing that a change in the in-plane stress from compressive to tensile tends to shift the magnetic transition by more than 60 K. The interplay between magnetic and elastic properties was further analyzed by ferromagnetic resonance, and we have found that ...
Unraveling the structural and electronic features of tungsten nitride (WNx) thin films H Singh, M Gupta, P Rajput, H Kumar Journal of Alloys and Compounds 1017, 179122 , 2025 2025 Citations: 2
Investigation of B2 phase formation by thermal annealing of Fe(Cu)/Rh multilayers VRRHK P. Negi, M. Gupta, R. Rawat, R. Joshi Journal of Magnetism and Magnetic Materials 613, 172671 , 2025 2025 Citations: 1
Role of spin-glass-like interfaces in exchange-biased MnN/Fe thin films grown on W buffer layers H Singh, M Gupta, H Prakash, H Kumar, H Fulara Applied Physics Letters 125, 092404 , 2024 2024
Formation of B2-ordered FeRh alloy thin films on annealing of pure and nitrogen doped Fe/Rh multilayers HK Preeti Negi, Mukul Gupta, Rajeev Rawat, Rajeev Joshi, Harsh Bhatt ... Journal of Magnetism and Magnetic Materials 581, 170941 , 2023 2023 Citations: 6
Role of nitrogen partial pressure, deposition rate and annealing on stability of β-W phase SLMHK H. Singh, M. Gupta, P. Gupta, R. F. S. Penacchio Applied Physics A 129 (312) , 2023 2023 Citations: 3
Structural and magnetic properties of FeRh films grown on MgO(001), MgO(011) and MgO(111) substrates DRC Hardeep Kumar, Sergio L. Morelhao, Gerson Pessotto, Hardepinder Singh ... Journal of Magnetism and Magnetic Materials 556, 169442 , 2022 2022 Citations: 11
Transformation of Au–Pd alloy nanoparticles to core-shell nanoparticles by electron irradiation B Tripathi, H Kumar, A Tripathi, S Kumar, SA Khan, G Lakshmi, AB Dey, ... Journal of Alloys and Compounds 832, 154944 , 2020 2020 Citations: 4
Improved hydrogen sensing behaviour in ion-irradiated Pd-Au alloy thin films H Kumar, A Tripathi, AB Dey, M Gupta, R Krishna, DK Avasthi Sensors and Actuators B: Chemical 301, 127006 , 2019 2019 Citations: 38
Strain effects on the magnetic order of epitaxial FeRh thin films H Kumar, DR Cornejo, SL Morelhao, S Kycia, IM Montellano, NR Alvarez, ... Journal of Applied Physics 124 (8) , 2018 2018 Citations: 33
Evidence of local structural influence on the shape driven magnetic anisotropy in electronically excited Ni nanoparticles embedded in SiO 2 matrix D Sarker, S Bhattacharya, H Kumar, P Srivastava, S Ghosh Scientific reports 8 (1), 1040 , 2018 2018 Citations: 4
Structural, morphological and magnetic characterization of electrodeposited Co–Fe–W alloys R Della Noce, AV Benedetti, M Magnani, EC Passamani, H Kumar, ... Journal of Alloys and Compounds 611, 243-248 , 2014 2014 Citations: 35
Enhancement in field emission current density of Ni nanoparticles embedded in thin silica matrix by swift heavy ion irradiation D Sarker, H Kumar, R Patra, D Kabiraj, DK Avasthi, SK Vayalil, SV Roth, ... Journal of Applied Physics 115 (17) , 2014 2014 Citations: 11
Use of conventional electrochemical techniques to produce crystalline FeRh alloys induced by Ag seed layer RD Noce, AV Benedetti, EC Passamani, H Kumar, DR Cornejo, ... Journal of alloys and compounds 573, 37-42 , 2013 2013 Citations: 1
Influence of current density on crystalline structure and magnetic properties of electrodeposited Co-rich CoNiW alloys AMP Sakita, EC Passamani, H Kumar, DR Cornejo, CS Fugivara, ... Materials Chemistry and Physics 141 (1), 576-581 , 2013 2013 Citations: 59
Evidence of coexistence of ferromagnetic and antiferromagnetic phases in nearly equiatomic FeRh H Kumar, MCA Fantini, DR Cornejo IEEE transactions on magnetics 49 (8), 4506-4509 , 2013 2013 Citations: 7
Stabilization of FeCo alloy phase in FeCo-SiO2 nanocomposites H Kumar, L G Aquilanti, S Ghosh, P Srivastava, D Kabiraj, D K Avasthi Advanced Materials Letters 4 (6), 390-397 , 2013 2013 Citations: 13
Role of Coulomb blockade and spin-flip scattering in tunneling magnetoresistance of FeCo-Si-O nanogranular films H Kumar, S Ghosh, D Bürger, L Li, S Zhou, D Kabiraj, DK Avasthi, ... Journal of Applied Physics 109 (7) , 2011 2011 Citations: 23
Ion beam-induced shaping of Ni nanoparticles embedded in a silica matrix: from spherical to prolate shape H Kumar, S Ghosh, DK Avasthi, D Kabiraj, A Mücklich, S Zhou, H Schmidt, ... Nanoscale research letters 6 (1), 155 , 2011 2011 Citations: 8
Magnetic and field emission studies of atom beam sputtered Ni: SiO2 granular films H Kumar, S Ghosh, DK Avasthi, D Kabiraj, NP Lalla, T Shripathi, JC Pivin Vacuum 85 (2), 139-144 , 2010 2010 Citations: 15
Microstructure, electrical, magnetic, and extraordinary Hall effect studies in Ni: SiO2 nanogranular films synthesized by atom beam sputtering H Kumar, S Ghosh, D Bürger, S Zhou, D Kabiraj, DK Avasthi, R Grötzschel, ... Journal of Applied Physics 107 (11) , 2010 2010 Citations: 12
MOST CITED SCHOLAR PUBLICATIONS
Influence of current density on crystalline structure and magnetic properties of electrodeposited Co-rich CoNiW alloys AMP Sakita, EC Passamani, H Kumar, DR Cornejo, CS Fugivara, ... Materials Chemistry and Physics 141 (1), 576-581 , 2013 2013 Citations: 59
Controlled reduction of size of Ag nanoparticles embedded in teflon matrix by MeV ion irradiation YK Mishra, VSK Chakravadhanula, U Schürmann, H Kumar, D Kabiraj, ... Nuclear Instruments and Methods in Physics Research Section B: Beam … , 2008 2008 Citations: 44
Improved hydrogen sensing behaviour in ion-irradiated Pd-Au alloy thin films H Kumar, A Tripathi, AB Dey, M Gupta, R Krishna, DK Avasthi Sensors and Actuators B: Chemical 301, 127006 , 2019 2019 Citations: 38
Structural, morphological and magnetic characterization of electrodeposited Co–Fe–W alloys R Della Noce, AV Benedetti, M Magnani, EC Passamani, H Kumar, ... Journal of Alloys and Compounds 611, 243-248 , 2014 2014 Citations: 35
Strain effects on the magnetic order of epitaxial FeRh thin films H Kumar, DR Cornejo, SL Morelhao, S Kycia, IM Montellano, NR Alvarez, ... Journal of Applied Physics 124 (8) , 2018 2018 Citations: 33
Role of Coulomb blockade and spin-flip scattering in tunneling magnetoresistance of FeCo-Si-O nanogranular films H Kumar, S Ghosh, D Bürger, L Li, S Zhou, D Kabiraj, DK Avasthi, ... Journal of Applied Physics 109 (7) , 2011 2011 Citations: 23
Magnetic and field emission studies of atom beam sputtered Ni: SiO2 granular films H Kumar, S Ghosh, DK Avasthi, D Kabiraj, NP Lalla, T Shripathi, JC Pivin Vacuum 85 (2), 139-144 , 2010 2010 Citations: 15
Stabilization of FeCo alloy phase in FeCo-SiO2 nanocomposites H Kumar, L G Aquilanti, S Ghosh, P Srivastava, D Kabiraj, D K Avasthi Advanced Materials Letters 4 (6), 390-397 , 2013 2013 Citations: 13
Compositional analysis of atom beam co-sputtered metal–silica nanocomposites by Rutherford backscattering spectrometry H Kumar, YK Mishra, S Mohapatra, D Kabiraj, JC Pivin, S Ghosh, ... Nuclear Instruments and Methods in Physics Research Section B: Beam … , 2008 2008 Citations: 13
Microstructure, electrical, magnetic, and extraordinary Hall effect studies in Ni: SiO2 nanogranular films synthesized by atom beam sputtering H Kumar, S Ghosh, D Bürger, S Zhou, D Kabiraj, DK Avasthi, R Grötzschel, ... Journal of Applied Physics 107 (11) , 2010 2010 Citations: 12
Structural and magnetic properties of FeRh films grown on MgO(001), MgO(011) and MgO(111) substrates DRC Hardeep Kumar, Sergio L. Morelhao, Gerson Pessotto, Hardepinder Singh ... Journal of Magnetism and Magnetic Materials 556, 169442 , 2022 2022 Citations: 11
Enhancement in field emission current density of Ni nanoparticles embedded in thin silica matrix by swift heavy ion irradiation D Sarker, H Kumar, R Patra, D Kabiraj, DK Avasthi, SK Vayalil, SV Roth, ... Journal of Applied Physics 115 (17) , 2014 2014 Citations: 11
Ion beam-induced shaping of Ni nanoparticles embedded in a silica matrix: from spherical to prolate shape H Kumar, S Ghosh, DK Avasthi, D Kabiraj, A Mücklich, S Zhou, H Schmidt, ... Nanoscale research letters 6 (1), 155 , 2011 2011 Citations: 8
Evidence of coexistence of ferromagnetic and antiferromagnetic phases in nearly equiatomic FeRh H Kumar, MCA Fantini, DR Cornejo IEEE transactions on magnetics 49 (8), 4506-4509 , 2013 2013 Citations: 7
Formation of B2-ordered FeRh alloy thin films on annealing of pure and nitrogen doped Fe/Rh multilayers HK Preeti Negi, Mukul Gupta, Rajeev Rawat, Rajeev Joshi, Harsh Bhatt ... Journal of Magnetism and Magnetic Materials 581, 170941 , 2023 2023 Citations: 6
Transformation of Au–Pd alloy nanoparticles to core-shell nanoparticles by electron irradiation B Tripathi, H Kumar, A Tripathi, S Kumar, SA Khan, G Lakshmi, AB Dey, ... Journal of Alloys and Compounds 832, 154944 , 2020 2020 Citations: 4
Evidence of local structural influence on the shape driven magnetic anisotropy in electronically excited Ni nanoparticles embedded in SiO 2 matrix D Sarker, S Bhattacharya, H Kumar, P Srivastava, S Ghosh Scientific reports 8 (1), 1040 , 2018 2018 Citations: 4
Role of nitrogen partial pressure, deposition rate and annealing on stability of β-W phase SLMHK H. Singh, M. Gupta, P. Gupta, R. F. S. Penacchio Applied Physics A 129 (312) , 2023 2023 Citations: 3
Unraveling the structural and electronic features of tungsten nitride (WNx) thin films H Singh, M Gupta, P Rajput, H Kumar Journal of Alloys and Compounds 1017, 179122 , 2025 2025 Citations: 2
Investigation of B2 phase formation by thermal annealing of Fe(Cu)/Rh multilayers VRRHK P. Negi, M. Gupta, R. Rawat, R. Joshi Journal of Magnetism and Magnetic Materials 613, 172671 , 2025 2025 Citations: 1
