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Questions related from Tapan Chatterji
It is well-known that the symmetry of the nonlinear optical susceptibility is strongly affected by a magnetization or an external applied magnetic field. Thus it is of considerable interest to...
06 June 2015 4,776 10 View
We studied the pressure dependence of the magnetoresistance in the magnetic semiconductor MnS2. We know that MnS2 undergoes a pressure induced structural transition associated with high-spin to...
12 December 2014 6,724 5 View
We normally think that the velocity of light is constant in all inertial frames is a postulate or the experimental result of Michelson-Morley experiment. But is it true that the Maxwell's...
09 September 2014 4,122 6 View
Superconductivity is essentially an emergent phenomenon of many body electron system. I am wondering how much size reduction can it stand. Certainly no superconductivity exists for a single atom...
08 August 2014 8,355 4 View
There are evidences of pressure-induced high-spin to low-spin transition in pyrite type MnS2 and MnTe2. Are there any other compounds which undergo such transition?
07 July 2014 7,496 0 View
Coherent diffraction is progressing enormously due to the advent of modern X-ray sources including XFEL. Can any one explain me how the old phase problem in crystallography be tackled by coherent...
06 June 2014 3,934 17 View
The IV-VI narrow band gap semiconductor GeTe undergoes a ferroelectric phase transition at about 600 K. At this transition the high temperature paraelectric cubic NaCl type phase undergoes a...
06 June 2014 7,144 4 View
The Cassimir effect between uncharged metallic surfaces originate from quantum-mechanical zero-point fluctuations of the electromagnetic field. For two parallel plates at a distance of about 10...
03 March 2014 694 4 View
We are all aware that water is the most important substance for life. Without it life in the form we know it as would not be possible. We also know that water behaves quite anomalously in many...
03 March 2014 4,825 9 View
Magnetic structures are usually determined by neutron powder diffraction. In difficult cases one may have to use single crystals or even polarized neutrons. Although X-ray magnetic scattering is...
03 March 2014 9,907 24 View
All physical laws are highly symmetric and cannot give rise to the observable and perceptible universe. The visible universe is far from being derivable from these laws. So there will never be any...
12 December 2013 418 57 View
It is well known that geometrical frustration of perfect tetrahedra and icosahedra lead to quasi-crystalline phases (see "Geometrical Frustration", J.-F. Sadoc and R. Mosseri, Cambridge (1999))....
12 December 2013 5,261 3 View
Gallium metal is somewhat anomalous because it's melting point is very low (Tm = 303 K) but its boiling point is relatively high Tb = 2477 K. That is say that its liquid state has got a very large...
10 October 2013 6,473 2 View
If you look at electrical conductivity of metals at ambient temperature and superconducting properties at low temperature then the above question arises naturally? This is also so for other type...
10 October 2013 9,412 68 View
Normally condensed matter theories statisfy hole electron symmetry. This is because this symmetry is present in the underlying basic theories. But experimentally it is known that the phenomenon of...
08 August 2013 2,336 18 View
If I have a good single domain crystal with a structure belonging to a non-centrosymmetric space group then ideally F(hkl) is not equal to F(-h,-k,-l). Is there any diffraction experiment that I...
05 May 2013 8,178 14 View
We have observed smaller volume in nanoparticles of half-doped manganites LCMO (La0.5Ca0.5MnO3) and PCMO(Pr0.5Ca0.5MnO3). We explained this by the effective surface tension of the nanoparticles....
05 May 2013 7,657 15 View
In most of the charge ordering phenomena (Fe3O4, NaV2O5, LaSr2Mn2O7, La0.5Ca0.5MnO3 etc.), the charge ordering is not complete. For example, in manganites, the Mn valence in the charge-ordered...
04 April 2013 8,869 1 View
We tried to determine the small atomic shifts in multiferroic YMnO3, HoMnO3 and LuMnO3 at the magnetic phase transition temperature by neutron powder diffraction and so far have not succeeded. We...
04 April 2013 7,981 8 View
It is not easy to distinguish non-centrosymmetric structure from the cetrosymmetric one, viz. P1 and P-1. There is no systematic absences to help. If you do the intensity statistics of a complete...
03 March 2013 5,196 40 View
The materials scientists have now become used to identify and analyze crystal structures by the Rietveld analysis of limited-Q diffraction data collected by in-house X-ray diffractometer. Rarely...
03 March 2013 5,207 5 View
