Mayukh Kumar Ray
@bose.res.in
Department Of Applied Science
Amity University, KOLKATA
EDUCATION
[2010 – 2016 ] Ph.D. in Physics, July 2016, Saha Institute Of Nuclear Physics, University Of
Calcutta.
Thesis title: Study of multifunctional properties associated with phase transition in
ferromagnetic Ni-Mn-based Heusler alloys.
Advisor: Prof. Sangam Banerjee (Google Scholar)
[2010 – 2011 ] Post M.Sc. in Physics.
Saha Institute Of Nuclear Physics, 1/AF, Bidhannagar, SaltLake, Sector I, Kolkata-
700064, India.
2009 – 2010 ] Completed Ph.D coursework (as HTRA) in Physics .
Indian Institute Of Technology, Madras, Chennai, Tamil Nadu 600036, India.
[2007 – 2009 ] M.Sc. in Physics.
Banaras Hindu University, Varanasi, Uttar Pradesh 221005, India.
Marks Obtained: 71.4 %
[2004 – 2007 ] B.Sc. in Physics (Honors) .
The University Of Burdwan, 6VQ2+PF3, Burdwan Rajbati, Raiganj, Burdwan,
West Bengal 713104, India.
Marks Obtained: 62 %
RESEARCH INTERESTS
Topological Materials, Dirac/Weyl Semimetals, Quantum Phase Transition,
Half-Heusler topological Material,
Magnetic and transport properties of strongly correlated systems,
Magnetocaloric and thermoelectric Materials.
Scopus Publications
Scholar Citations
Scholar h-index
Scholar i10-index
Scopus Publications
M Modak, Mayukh K Ray, S Mondal, B Maji, K Bagani, A Bhattacharyya, and S Banerjee
IOP Publishing
The influence of martensite and austenite phase volume fractions on the magnetoresistance have been studied across the first order martensite transformation of the Ni 44 Cu 2 Mn 43 In 11 compound. The different phase volume fractions are calculated by measuring the resistivity as a function of temperature and magnetic field. Our experiment reveals that the field-induced austenite phase fraction ( f IA ) at any temperature depends on the availability and instability of the martensite phase fraction ( f M ) at that temperature. This f IA is found to contribute most significantly to the observed large magnetoresistance (MR), while the contributions from parent martensite and austenite phase fractions are negligible. It has been found that the MR does not depend linearly on the f IA . On application of a magnetic field, the ascending and descending branch of the f IA follows a different power law, giving rise to hysteresis in the MR. Supplementary material for this article is available online (Some figures may appear in colour only in the online journal)
Sampad Mondal, M. Modak, B. Maji, Mayukh K. Ray, S. Mandal, Swapan K. Mandal, M. Sardar, and S. Banerjee
American Physical Society (APS)
We report a study of magnetization, resistivity, magnetoresistance, and specific heat of the pyrochlore iridate ${({\\mathrm{Eu}}_{1\\ensuremath{-}x}{\\mathrm{Nd}}_{x})}_{2}{\\mathrm{Ir}}_{2}{\\mathrm{O}}_{7}$ with $x=0.0$, 0.5 and 1.0, where spin-orbit coupling, electronic correlation, magnetic frustration, and Kondo scattering coexist. The metal insulator transition temperature (${T}_{MI}$) decreases with increase in Nd content, but always coincides with the magnetic irreversibility temperature (field-induced moment). Resistivity below ${T}_{MI}$ does not fit with either activated (gap) or any power-law (gapless) dependence. The Curie constant shows the surprising result that Nd induces singlet correlation (reduction of paramoment) in the Ir sublattice. Magnetoresistance is negative at low temperatures below 10 K and increases strongly with increase in $x$, and varies quadratically with field switching over to a linear dependence above 50 kOe. Low-temperature specific heat shows a Schottky peak, coming from Nd moments, showing the existence of a doublet split in the Nd energy level, arising from the $f\\ensuremath{-}d$ exchange interaction. All materials show the presence of a linear specific heat in the insulating region. The coefficient of linear specific heat for $x=0.0$ does not vary with the external magnetic field, but varies superlinearly for $x=1.0$ materials. We argue that linear specific heat probably rules out weakly correlated phases such as Weyl fermions. We propose that with the introduction of Nd at the Eu site, the system evolves from a chiral spin liquid with gapless spinon excitations with a very small charge gap to a Kondo-type interaction superposed on a chiral spin liquid coexisting with long-range antiferromagnetic ordering. A huge increase of magnetoresistance with increase in Nd concentrations shows the importance of Kondo scattering in the chiral spin-liquid material by rare-earth moments.
Mayukh K. Ray, Bibekananda Maji, Kapil Motla, Sajilesh K. P., and R. P. Singh
AIP Publishing
We report anomalous magnetic reversal (MR)/negative magnetization (NM) state associated with the field induced switching of orbital moment ( μ L S m) of the Sm atom. This material shows an antiferromagnetic transition at Neel temperature ( T N ∼ 240 K) followed by a NM state in between compensation temperatures ( T ∗ and T ∗ ∗). The MR/NM state vanishes above 12.5 kOe, while T ∗ and T ∗ ∗ follow opposite magnetic field dependency in field cooled cooling (FCC) magnetization. In the high field ( H > 20 kOe), the thermo-magnetization [ M ( T )] curve produces a mirror like inversion in magnetization within ( T ∗ − T ∗ ∗) with respect to its low field FCC counterpart. Within the NM region, the exchange bias field ( H E B) changes its sign across compensation temperatures for suitable field cooling (FC). We estimated a large FC inverse and conventional H E B of 8 and − 4.8 kOe at T = 130 K. Furthermore, the magnetic entropy change ( Δ S m) and adiabatic temperature change ( Δ T a d) calculated from the specific heat [ C p ( T , H )] measurements also show sign reversal at T ∗ ∗. These unusual behaviors are explained in terms of field induced switching of μ L S m, which is oppositely coupled to the spin moment of Sm ( μ S S m), Mn–Mn/Sm exchange interactions, and polarized conduction electron moment ( μ S C E P). Additionally, C p ( T , H ) exhibit Schottky anomaly around 3 K due to Zeeman splitting of Sm energy levels.
M Modak, Mayukh K Ray, S Mondal, B Maji, K Bagani, A Bhattacharyya, and S Banerjee
IOP Publishing
Abstract The influence of martensite and austenite phase volume fractions on the magnetoresistance have been studied across the first order martensite transformation of the Ni44Cu2Mn43In11 compound. The different phase volume fractions are calculated by measuring the resistivity as a function of temperature and magnetic field. Our experiment reveals that the field-induced austenite phase fraction ( f IA ) at any temperature depends on the availability and instability of the martensite phase fraction ( f M ) at that temperature. This f IA is found to contribute most significantly to the observed large magnetoresistance (MR), while the contributions from parent martensite and austenite phase fractions are negligible. It has been found that the MR does not depend linearly on the f IA . On application of a magnetic field, the ascending and descending branch of the f IA follows a different power law, giving rise to hysteresis in the MR.
M. Modak, B. Maji, S. Mondal, M.K. Ray, and S. Banerjee
Elsevier BV
Bibekananda Maji, M. Modak, S. Mondal, M.K. Ray, and K.G. Suresh
Elsevier BV
B. Ghosh, K. Bagani, S. Majumder, M. Modak, M.K. Ray, M. Sardar, and S. Banerjee
Elsevier BV
Bibekananda Maji, Mayukh K. Ray, M. Modak, S. Mondal, K.G. Suresh, and S. Banerjee
Elsevier BV
Mayukh K. Ray, I M Obaidat, and Sangam Banerjee
IOP Publishing
In this work, we studied the magnetic entropy change (ΔSM) across the martensite transformation (MT) in Mn-rich Ni46Cu2Mn43ln11 alloy. This compound undergoes a MT and a magnetic phase transition around the temperatures (TM=) 272 K and (TCA=) 325 K, respectively. A large field induced shift (=0.28 K/kOe) of the MT temperatures is observed. An application of magnetic field (H =) of 50 kOe causes a large ΔSM of 20 J/kg-K and -4.4 J/kg-K around TM and TCA, respectively. We also found that the change in magnetic field induced isothermal ΔSM(H)T is mainly depends on the induced austenite phase fraction by the applied magnetic field at that temperature. Possible reasons for the observed behaviours are comprehensively discussed.
Sampad Mondal, M. Modak, M.K. Ray, Swapan K. Mandal, M. Sardar, and S. Banerjee
Elsevier BV
C. Nayek, M. K. Ray, A. Pal, I. M. Obaidat, and P. Murugavel
Springer Science and Business Media LLC
Mayukh K. Ray, Bibekananda Maji, Ihab Obaidat, and Sangam Banerjee
AIP Publishing
We conducted the temperature (T) and magnetic field (H) dependence of resistivity (ρ) on Ni44Co2Mn43In11 compound under the magnetic field (H=) 0-70 kOe in the temperature range T=150-380 K. Several novel anomalies are observed in the ρ(T,H) behaviour of this compound which upto our knowledge were not reported earlier in these systems. An unusual change in ρ(T) associated with a positive manetoresistance (MR) is also observed just above the martensite transformation (MT) in the temperature range of T=308-320 K. In addition, an anomalous field dependence of the MR is observed in temperature region T=305-310 K, where ρ increases with H after reaching minimum. Furthermore, a large MR up to -65 % is observed across its room temperature MT which can be beneficial for practical applications. The possible origin of the observed MR behaviour is discussed in terms enhanced magnetic scattering.
Mayukh K. Ray, Bibekananda Maji, M. Modak, and S. Banerjee
Elsevier BV
Mayukh K. Ray, K. Bagani, and S. Banerjee
Elsevier BV
K. Bagani, M. K. Ray, M. Sardar, and S. Banerjee
American Physical Society (APS)
Mayukh K. Ray, K. Bagani, P. K. Mukhopadhyay, and S. Banerjee
IOP Publishing
The magnetic ground state of the Mn50Ni38.5Sn11.5 alloy is investigated through dc/ac magnetization and low-temperature specific-heat measurements. The dc and ac magnetization measurements indicate that the system can be identified as a cluster spin glass (CSG) phase in a ferromagnetic (FM) background, and as a conjunction of these two phases an exchange bias effect (EBE) is observed in this system. The presence of coexisting phases is further supported by our measurement. We attribute the existence of the CSG phase to the antiferromagnetic (AFM) interaction arising from the Mn-Mn antisite disorder which further enhances through martensite transformation. The anomalous increase of Cp below 0.7 K is due to the nuclear Schottky anomaly arising from the hyperfine splitting of the nuclear levels of Mn atoms. Detailed reasons for the observed behaviours are discussed in the paper.
Bibekananda Maji, Mayukh K. Ray, K. G. Suresh, and S. Banerjee
AIP Publishing
We report multiple first order magnetic transitions in TbMn2Si2 as evidenced by the thermal hysteresis in the M-T data and the Arrott plots. Metamagnetic transitions are observed at various temperatures as a result of the antiferromagnetic to ferromagnetic transition of the Mn sublattice. Very interestingly, the compound shows significant exchange bias field of about 600 Oe at 5 K, which is attributed to the formation of small domains or regions with ferromagnetic and antiferromagnetic interactions. Furthermore, a large magnetocaloric effect has been found at relatively low fields at both the transition regions. Maximum magnetic entropy changes (−ΔSM) of 7.2 and 5.4 J kg−1 K−1 have been observed at 68 K and at 48 K, respectively, at 20 kOe.
Mayukh K Ray, Bibekananda Maji, K Bagani, and S Banerjee
IOP Publishing
In this investigation we show that the optimum substitution of Ni by Co and Cu can bring the martensite transition temperature (TM = 390 K) of Ni46Mn43In11 alloy close to room temperature as well as greatly influence applicable magnetic and transport properties. In contrast to the parent alloy, a ferromagnetic austenite phase is induced in these substituted alloys. A huge exchange bias field of up to 1615 Oe was observed for a field-cooled hysteresis loop at 5 K in the Ni44Cu2Mn43In11 alloy. A giant magnetic entropy change of 20.8 J kg−1K−1 at a field change of 70 kOe and a giant negative magneto-resistance of 57% at ΔH = 30 kOe was also observed for the Ni44Co2Mn43In11 alloy. Possible reasons for the observed behaviours are comprehensively discussed.
Mayukh K. Ray, K. Bagani, R.K. Singh, B. Majumdar, and S. Banerjee
Elsevier BV
Mayukh K. Ray, K. Bagani, and S. Banerjee
Elsevier BV
Kousik Bagani, Mayukh K. Ray, Biswarup Satpati, Nihar R. Ray, Manas Sardar, and Sangam Banerjee
American Chemical Society (ACS)
We report the observation of enhanced magnetization in graphene oxide (GO) after thermal annealing. We have also proposed that this enhancement in magnetization is due to the increased density of zigzag edges. We conjecture that on annealing the random epoxy groups in the native GO migrate over the GO surface by acquiring thermal energy and self-assemble to form several long chains of epoxy groups. Subsequently, upon thermal reduction the GO sheet is unzipped along these long chains giving rise to more zigzag edges, resulting in enhancement of magnetization. We also found out that the density of epoxy groups plays an important role in the unzipping process. If the density of epoxy groups is low, then unzipping of GO is not possible. Chemical reduction of GO does not favor unzipping.
Mayukh K. Ray, K. Bagani, R. K. Singh, B. Majumdar, and S. Banerjee
AIP Publishing
The Ni50Mn37Sb13 ribbons were prepared by melt-spinning technique to overcome the brittleness of bulk. A single phase austenite with L21 structure was confirmed in the as-spun and annealed ribbons at room temperature similar to bulk. We observe increments in the martensite transformation temperature (TM) from 238 K to 252 K and in Curie temperature of austenite phase (TCA) from 336 K to 342 K after annealing the as-spun ribbon. The exchange bias, magnetic entropy change (ΔSM), and magnetoresistance are found to increase from 380 Oe to 415 Oe, 1 J/kg-K to 3 J/kg-K (ΔH=50 kOe), and −4% to −13% (ΔH=50 kOe), respectively, after annealing the as-spun ribbon. The possible reasons for observed behaviour are discussed.
M. K. Ray, K. Bagani, B. Ghosh, and S. Banerjee
AIP
Effect of Fe doping on the martensitic transition and exchange bias in Ni50Mn35Sn15 was investigated. The experimental results show that the martensitic transition temperature increase upon substitution of Sn by Fe. The exchange bias is also enhanced at low temperature. This indicates the Fe plays a major role in these enhancements. We shall discuss this aspect in this manuscript.
B. Ghosh, K. Bagani, M. K. Ray, M. Sardar, and S. Banerjee
AIP
In this manuscript we report magnetic phases as a function of temperature below 300 K in CaFeO3 nanoparticles. The observed exchange bias could be explained invoking magnetically core-shell structure. The core of the particle transforms from A-type antiferromagnetic to Ferromagnetic and back to spiral antiferromagnetic state as one lowers the temperature. This re-entrant behavior could be established from the exchange bias data.
K. Bagani, M. K. Ray, B. Ghosh, N. Gayathri, M. Sardar, and S. Banerjee
AIP
We report magnetism in ball milled Cu:TiO2 particles. We have measured X-ray diffraction, Zero Field Cooled (ZFC), Field Cooled (FC) magnetization and magnetic hysteresis of these ball milled sample. The observed enhanced magnetism in Cu:TiO2 has been explained invoking core-shell structure of this system. We observe bifurcation in the ZFC-FC curve and maxima in the ZFC curve indicating superparamagnetic nature of this ball milled particle.