Contrasting magnetic response between magnetic-glass and reentrant spin-glass (2008)
Roy, S. B., Chattopadhyay, M. K.
Magnetic-glass is a recently identified phenomenon in various classes of magnetic systems undergoing a first order magnetic phase transition. We shall highlight here a few experimentally determined...
Kumar, Kranti, Pramanik, A. K., Banerjee, A., Chaddah, P., Roy, S. B., Park, S., ...
Coexisting ferromagnetic and antiferromagnetic phases over a range of temperature as well as magnetic field have been reported in many materials of current interest, showing disorder-broadened 1st...
Chaddah, P., Banerjee, A., Roy, S. B.
Coexisting ferromagnetic (FM) and antiferromagnetic (AFM) phases over a range of temperature (T) and magnetic field (H), have been reported in many materials. The 1st order FM-AFM transition is...
Rai, S., Tiwari, M. K., Lodha, G. S., Modi, M. H., Chattopadhyay, M. K., Majumdar, S., ...
We report a detailed study of surface and interface properties of pulsed-laser deposited NiMnSb films on Si (100) substrate as a function of film thickness. As the thickness of films is reduced below...
Chandra, L. S. Sharath, Mukherjee, Kaustav, Ganesan, V., Banerjee, A., Chaddah, P., Chattopadhyay, M. K., ...
Field variation of heat capacity at fixed temperatures is investigated to identify the origin of the field induced first order phase transition in polycrystalline Ce(Fe$_{0.094}$Al$_{0.04}$)$_2$...
Chattopadhyay, M. K., Roy, S. B., Chaddah, P.
We present results of dc magnetization and magnetic relaxation study showing the kinetic arrest of a first order ferromagnetic to antiferromagnetic transition in Ce(Fe$_{0.96}$Ru$_{0.04}$)$_2$. This...
Unusual transport properties of ferromagnetic Heusler alloy Co$_2$TiSn (2005)
Majumdar, S., Chattopadhyay, M. K., Sharma, V. K., Sokhey, K. J. S., Roy, S. B., Chaddah, P.
We report results of magnetization, zero field resistivity and magnetoresistance measurements in ferromagnetic Heusler alloy Co$_2$TiSn. There is a striking change in the character of electron...
Roy, S. B., Chattopadhyay, M. K., Chaddah, P., Nigam, A. K.
Very sharp magnetization step is observed across the field induced antiferromagnetic to ferromagnetic transition in various doped-CeFe$_2$ alloys, when the measurement is performed below 5K. In the...
First order magnetic transition in CeFe$_2$ alloys: Phase-coexistence and metastability (2003)
Roy, S. B., Perkins, G. K., Chattopadhyay, M. K., Nigam, A. K., Sokhey, K. J. S., Chaddah, P., ...
First order ferromagnetic (FM) to antiferromagnetic (AFM) phase transition in doped-CeFe$_2$ alloys is studied with micro-Hall probe technique. Clear visual evidence of magnetic phase-coexistence on...
Relaxation under Supercooling of the Disordered Vortex State in Doped CeRu2 Alloy (2003)
Chattopadhyay, M. K., Sokhey, K. J. S., Roy, S. B., Chaddah, P.
Relaxation in magnetisation of metastable states is reported. The states are prepared by supercooling a Ce(Ru, 5% Nd)2 alloy sample to different extents through similar paths in the H-T space, and...
Interesting thermomagnetic history effects in the antiferromagnetic state of SmMn_2Ge_2 (2002)
Roy, S. B., Chaudhary, S., Chattopadhyay, M. K., Chaddah, P., Sampathkumaran, E. V.
We present results of magnetization measurements showing that the magnetic response of the antiferromagnetic state of SmMn_2Ge_2 depends on the path used in the field(H)-temperature(T) phase space to...
Resistivity and thermoelectric power measurements on CeFe$_2$ and its pseudobinaries (2002)
Chattopadhyay, M. K., Manekar, Meghmalhar, Singh, Kanwal Jeet, Chaudhary, Sujeet, Roy, S. B., Chaddah, P.
Resistivity and thermoelectric power (TEP) measurements on CeFe$_2$ and two of its pseudo-binaries Ce(Fe, 5% Ir)$_2$ and Ce(Fe, 7% Ru)$_2$ between 78K and 275K are reported. The resistivity data are...
Thermomagnetic history effects in SmMn$_2$Ge$_2$ (2002)
Chaudhary, Sujeet, Chattopadhyay, M. K., Singh, Kanwal Jeet, Roy, S. B., Chaddah, P., Sampathkumaran, E. V.
The intermetallic compound SmMn$_2$Ge$_2$, displaying multiple magnetic phase transitions, is being investigated in detail for its magnetization behavior near the 145 K first order ferromagnetic to...
Singh, Kanwal Jeet, Chaudhary, Sujeet, Chattopadhyay, M. K., Manekar, M. A., Roy, S. B., Chaddah, P.
The magnetotransport behaviour is investigated in detail across the first order magnetic phase transition from ferromagnetic to antiferromagnetic state in polycrystalline...
Interesting magnetic properties of Fe$_{1-x}$Co$_x$Si alloys (2001)
Chattopadhyay, M. K., Roy, S. B., Chaudhary, Sujeet
Solid solution between nonmagnetic narrow gap semiconductor FeSi and diamagnetic semi-metal CoSi gives rise to interesting metallic alloys with long-range helical magnetic ordering, for a wide range...
Roy, S. B., Radzyner, Y., Giller, D., Wolfus, Y., Shaulov, A., Chaddah, P., ...
We highlight interesting thermomagnetic history effects across the transition line between the (quasi) ordered and disordered vortex states in single crystal YBa$_2$Cu$_3$O$_{7-\delta}$, and argue...
Manekar, M. A., Chaudhary, S., Chattopadhyay, M. K., Singh, K. J., Roy, S. B., Chaddah, P.
Taking the pseudobinary C15 Laves phase compound Ce(Fe$_{0.96}$Al$_{0.04}$)$_2$ as a paradigm for studying a ferromagnetic to antiferromagnetic phase transition, we present interesting thermomagnetic...
Manekar, M. A., Chaudhary, S., Chattopadhyay, M. K., Singh, K. J., Roy, S. B., Chaddah, P.
Results of dc magnetization study are presented showing interesting thermomagnetic history effects across the antiferromagnetic to ferromagnetic transition in Ce(Fe$_{0.96}$Al$_{0.04})_2$....
Peak effect in the vortex state of V$_3$Si: a study of history dependence (2000)
Chaudhary, Sujeet, Rajarajan, A. K., Singh, Kanwal Jeet, Roy, S. B., Chaddah, P.
We present results of transport properties measurement on a single crystal of V$_3$Si showing distinct signature of peak-effect in its vortex state. The field variation of the electrical resistance...
First order metamagnetic transition in CeFe$_2$ based pseudobinary alloys (2000)
Manekar, Meghmalhar, Chaudhary, Sujeet, Chattopadhyay, M. K., Singh, Kanwal Jeet, Roy, S. B., Chaddah, P.
We present results of dc magnetisation study showing that the low temperature antiferromagnetic state in various CeFe$_2$-based pseudobinary alloys can be transformed into ferromagnetic state through...
Manekar, Meghmalhar, Roy, S. B., Chaddah, P.
We present results of ac susceptibility measurements highlighting the presence of thermal hysteresis and phase coexistence across the ferro-to antiferromagnetic transition in various CeFe$_2$ based...
Vortex Matter and its Phase Transitions (2000)
The mixed state of type II superconductors has magnetic flux penetrating the sample in the form of vortices, with each vortex carrying an identical quantum of flux. These vortices generally form a...
Peak effect in CeRu$_2$:history dependence and supercooling (2000)
Roy, S. B., Chaddah, P., Chaudhary, Sujeet
We present experimental results on single crystal CeRu$_2$ showing that the extent of history dependence of peak-effect depends on the path followed in the space of field (H) and temperature (T). The...
Chaudhary, Sujeet, Rajarajan, A. K., Singh, Kanwal Jeet, Roy, S. B., Chaddah, P.
We present results of transport measurements showing distinct path dependence of the electrical resistance in the superconducting vortex state of single crystal samples of CeRu$_2$ and V$_3$Si....
Metastabilities in vortex matter (1999)
We extend the classical theory for supercooling across first order phase transitions to the case when both density and temperature are control variables. The observable region of metastability then...
Supercooling across first-order phase transitions in vortex matter (1999)
Hysteresis in cycling through first-order phase transitions in vortex matter, akin to the well-studied phenomenon of supercooling of water, has been discussed in literature. Hysteresis can be seen...
Raychaudhuri, P., Nigam, A. K., Pinto, R., Chaudhary, Sujeet, Roy, S. B.
We study the spin polarised tunnelling mechanism through magnetisation and magnetoresistance in the granular polycrystalline colossal magnetoresistive manganite, La0.55Ho0.15Sr0.3MnO3. This system...
An Assessment of JFM in Regeneration and Management of Degraded Sal Forest in West Bengal (1998)
From the Author's Paper: "India, like many other Asian countries, is responding to forest degradation and food and energy shortages by experimenting with new forms of resource management. This paper...
On the interesting magnetic behaviour of UFe2, CeFe2 and their pseudobinary compounds (1989)
Roy, S.B., Williams, G., Coles, B.R.
New results for the magnetic properties of U (Fe, Al )2, (U, Ce )Fe2, and for the effects of U substitution for Ce on the anomalous behaviour of some Ce (Fe, X)2 alloys (where X = Co or Al) make...
On the interesting magnetic behaviour of UFe2, CeFe2 and their pseudobinary compounds (1989)
Roy, S.B., Williams, G., Coles, B.R.
New results for the magnetic properties of U (Fe, Al )2, (U, Ce )Fe2, and for the effects of U substitution for Ce on the anomalous behaviour of some Ce (Fe, X)2 alloys (where X = Co or Al) make...
On the interesting magnetic behaviour of UFe2, CeFe2 and their pseudobinary compounds (1989)
Roy, S.B., Williams, G., Coles, B.R.
New results for the magnetic properties of U (Fe, Al )2, (U, Ce )Fe2, and for the effects of U substitution for Ce on the anomalous behaviour of some Ce (Fe, X)2 alloys (where X = Co or Al) make...
Wasir, H S, Mahapatra, R K, Bhatia, M L, Roy, S B, Sannerstedt, R
The antiarrhythmic effect of the cardioselective beta-adrenoceptor blocking agent metoprolol, given intravenously, was studied in 44 patients with various tachyarrhythmias, including patients with...
Effects of high altitude hypoxia on left ventricular systolic time intervals in man.
Balasubramanian, V, Kaushik, V S, Manchanda, S C, Roy, S B
Effects of high altitude hypoxia on systolic time intervals were examined in 34 healthy men: 20 sea level residents studied at rest and at the end of 3 minutes steady isometric (handgrip) exercise at...
Haemodynamic studies in high altitude pulmonary oedema.
Roy, S B, Guleria, J S, Khanna, P K, Manchanda, S C, Pande, J N, Subba, P S