AK Raychaudhuri

Effect of grain boundaries on the local electronic transport in nanostructured films of colossal magnetoresistive manganites (2007)

We have studied the resistance of metallic nanowires (silver and copper) as a function of the wire diameter in the temperature range 4.2 K-300 K. The nanowires with an average diameter of 15 nm-200...

Kar, S, Sarkar, J, Ghosh, B, Raychaudhuri, AK

We have studied the spatially resolved local electronic properties of nanostructured films of a colossal magnetoresistive (CMR) material by local conductance mapping (LCMAP) using a variable...

Piezoresistivity in films of nanocrystalline manganites (2007)

Sarkar, Jayanta, Raychaudhuri, AK

Rare earth manganites having perovskite structure are susceptible to lattice strain. So far most investigations have been done with hydrostatic pressure or biaxial strain. We have observed that hole...

Thermal Fluctuations in Histone During Denaturation (2007)

Nagapriya, KS, Raychaudhuri, AK, Shivashankar, GV

In this paper, we address the issue of thermal fluctuations during the thermal denaturation of linker histone H1 which is the basic ingredient of chromatin assembly. We measure the thermal...

Adhesion behaviour of self-assembled alkanethiol monolayers on silver at different stages of growth (2007)

Sai, Phanindra T, Raychaudhuri, AK

We studied the development of interfacial energy $\gamma$ of alkanethiol self-assembled monolayers on Ag/mica substrates by force-displacement spectroscopy using an atomic force microscope....

Distinct levels in the nanoscale organization of DNA-histone complex revealed by its mechanical unfolding (2007)

Soni, GV, Brar, Loveleen, Hameed, Feroz M, Raychaudhuri, AK, Shivashankar, GV

Mechanical unfolding of nanoscale DNA-histone complex, using an atomic force microscope, shows a stepwise disassembly of histones from the nucleosome. A quantitative analysis of the rupture jump...

Stability of metal nanowires $(d \geq 15 nm)$ against electromigration (2007)

Bora, A, Bid, A, Raychaudhuri, AK

We have studied stability of metal nanowires against electromigration damage when they are subjected to high current density. Silver nanowires of diameter ranging from 15 nm to 100 nm were...

Debye Temperature of Metallic Nanowires—An Experimental Determination from the Resistance of Metallic Nanowires in the Temperature Range 4.2 K-300 K (2007)

Effect of grain boundaries on the local electronic transport in nanostructured films of colossal magnetoresistive manganites (2007)

We have studied the resistance of metallic nanowires (silver and copper) as a function of the wire diameter in the temperature range 4.2 K-300 K. The nanowires with an average diameter of 15 nm-200...

Kar, S, Sarkar, J, Ghosh, B, Raychaudhuri, AK

We have studied the spatially resolved local electronic properties of nanostructured films of a colossal magnetoresistive (CMR) material by local conductance mapping (LCMAP) using a variable...

Piezoresistivity in films of nanocrystalline manganites (2007)

Sarkar, Jayanta, Raychaudhuri, AK

Rare earth manganites having perovskite structure are susceptible to lattice strain. So far most investigations have been done with hydrostatic pressure or biaxial strain. We have observed that hole...

Thermal Fluctuations in Histone During Denaturation (2007)

Nagapriya, KS, Raychaudhuri, AK, Shivashankar, GV

In this paper, we address the issue of thermal fluctuations during the thermal denaturation of linker histone H1 which is the basic ingredient of chromatin assembly. We measure the thermal...

Distinct levels in the nanoscale organization of DNA-histone complex revealed by its mechanical unfolding (2007)

Soni, GV, Brar, Loveleen, Hameed, Feroz M, Raychaudhuri, AK, Shivashankar, GV

Mechanical unfolding of nanoscale DNA-histone complex, using an atomic force microscope, shows a stepwise disassembly of histones from the nucleosome. A quantitative analysis of the rupture jump...

Adhesion behaviour of self-assembled alkanethiol monolayers on silver at different stages of growth (2007)

Sai, Phanindra T, Raychaudhuri, AK

We studied the development of interfacial energy $\gamma$ of alkanethiol self-assembled monolayers on Ag/mica substrates by force-displacement spectroscopy using an atomic force microscope....

Colossal electroresistance in the ferromagnetic insulating state of single crystal $Nd_{0.7}Pb_{0.3}MnO_3$ (2007)

Jain, Himanshu, Raychaudhuri, AK, Ghosh, Nilotpal, Bhat, HL

Colossal electroresistance (CER) has been observed in the ferromagnetic insulating (FMI) state of a manganite. Notably, the CER in the FMI state occurs in the absence of magnetoresistance (MR)....

Investigation of the Effect of Microstructure and Grain Boundaries in Nanostructured CMR Thin Films Using Scanning Tunneling Microscopy (STM) and Local Conductance Map (LCMAP) (2006)

Kar, Sohini, Sarkar, Jayanta, Raychaudhuri, AK

We have investigated the spatially resolved local electronic properties of a nanostructured film of a colossal magnetoresistive (CMR) material by local conductance mapping (LCMAP) using a variable...

Colossal electroresistance and current induced switching in ferromagnetic insulating state of $La_{0.82}Ca_{0.18}MnO_3$ (2006)

Jain, Himanshu, Raychaudhuri, AK

Colossal electroresistance and current induced resistivity switching have been measured in the ferromagnetic insulating FMI state of single crystal manganite $La_{0.82}Ca_{0.18}MnO_3$. The sample has...

Direct observation of large temperature fluctuations during DNA thermal denaturation (2006)

Nagapriya, KS, Raychaudhuri, AK, Chatterji, Dipankar

In this paper we report direct measurement of large low frequency temperature fluctuations in double stranded (ds) DNA when it undergoes thermal denaturation transition. The fluctuation, which occurs...

1/f Noise in nanowires (2006)

Low-temperature polymer precursor-based synthesis of nanocrystalline particles of lanthanum calcium manganese oxide $(La_{0.67}Ca_{0.33}MnO_{3})$ with enhanced ferromagnetic transition temperature (2006)

We have measured the low-frequency resistance fluctuations (1 mHz < f < 10 Hz) in Ag nanowires of diameter 15 nm ${\leq}d{\leq}$200 nm at room temperature. The power spectral density (PSD) of the...

Low-temperature polymer precursor-based synthesis of nanocrystalline particles of lanthanum calcium manganese oxide $(La_{0.67}Ca_{0.33}MnO_{3})$ with enhanced ferromagnetic transition temperature (2006)

We report a simple modified polymeric precursor route for the synthesis of highly crystalline and homogenous nanoparticles of lanthanum calcium manganese oxide (LCMO). The LCMO phase formation was...

Direct observation of large temperature fluctuations during DNA thermal denaturation (2006)

We report a simple modified polymeric precursor route for the synthesis of highly crystalline and homogenous nanoparticles of lanthanum calcium manganese oxide (LCMO). The LCMO phase formation was...

Nagapriya, KS, Raychaudhuri, AK, Chatterji, Dipankar

In this paper we report direct measurement of large low frequency temperature fluctuations in double stranded (ds) DNA when it undergoes thermal denaturation transition. The fluctuation, which occurs...

Colossal electroresistance and current induced switching in ferromagnetic insulating state of $La_{0.82}Ca_{0.18}MnO_3$ (2006)

Jain, Himanshu, Raychaudhuri, AK

Colossal electroresistance and current induced resistivity switching have been measured in the ferromagnetic insulating FMI state of single crystal manganite $La_{0.82}Ca_{0.18}MnO_3$. The sample has...

Investigation of the Effect of Microstructure and Grain Boundaries in Nanostructured CMR Thin Films Using Scanning Tunneling Microscopy (STM) and Local Conductance Map (LCMAP) (2006)

Kar, Sohini, Sarkar, Jayanta, Raychaudhuri, AK

We have investigated the spatially resolved local electronic properties of a nanostructured film of a colossal magnetoresistive (CMR) material by local conductance mapping (LCMAP) using a variable...

Temperature dependence of the gap in the density of states near the Fermi level in a hole doped manganite (2005)

Kar, Sohini, Mitra, J, Raychaudhuri, AK

In this paper, we report a model-based quantitative analysis of temperature dependent scanning tunneling spectroscopy (STS) data taken on epitaxial thin films of the hole doped manganite...

Proceedings of the National Conference on Nanoscience and Technology - Part II - Foreword (2005)

Proceedings of the National Conference on Nanoscience and Technology Part I - National Chemical Laboratory - Pune - 7-8 march 2005 - Foreword (2005)

The dawn of 21st century is marked by the birth of a new science Nanoscience and the emanating Nanotechnology. Nanostructures are intermediate in size between molecular and mesoscopic structures...

Electronic transport in nanostructured thin films of perovskite manganite $La_{0.67}Ca_{0.33}Mno_{3}$: role of grain boundaries (2005)

The dawn of 21st century is marked by the birth of a new science Nanoscience and the emanating Nanotechnology. Nanostructures are intermediate in size between molecular and mesoscopic structures...

Paranjape, Mandar A, Shankar, Shantha K, Raychaudhuri, AK

We have prepared nanostructured thin films of $La_{0.67}Ca_{0.33}Mno_{3}$, with an average grain size of around 18 nm, using the chemical solution deposition method. The film has a metal-insulator...

Observation of large low-frequency resistance fluctuations in metallic nanowires: Implications on its stability (2005)

Temperature dependence of density of states near the Fermi level in a strain-free epitaxial film of the hole-doped manganite $La_{0.7}Ca_{0.3}MnO_{3}$ (2005)

We have measured the low frequency (1 mHz \leq f \leq 10 Hz) resistance fluctuations in metallic nanowires (diameter 15 nm to 200 nm) in the temperature range 77 K to 400 K. The nanowires were grown...

Mitra, J, Paranjape, Mandar, Raychaudhuri, AK, Mathur, ND, Blamire, MG

Scanning tunneling spectroscopy measurements were performed on an epitaxial thin film of $La_{0.7}Ca_{0.3}MnO_{3}$ grown on a $NdGaO_{3}$ substrate. The temperature variation of the density of states...

Collapse of the charge-ordering state at high magnetic fields in the rare-earth manganite $Pr_{0.63}Ca_{0.37}MnO_3$ (2005)

Nagapriya, KS, Raychaudhuri, AK, Bansal, Bhavtosh, Venkataraman, V, Parashar, Sachin, Rao, CNR

We have investigated the specific heat and resistivity of a single crystal of $Pr_{0.63}Ca_{0.37}MnO_3$ around the charge ordering (CO) transition temperature, $T_{CO}$, in the presence of high...

Temperature dependence of density of states near the Fermi level in a strain-free epitaxial film of the hole-doped manganite $La_{0.7}Ca_{0.3}MnO_{3}$ (2005)

Mitra, J, Paranjape, Mandar, Raychaudhuri, AK, Mathur, ND, Blamire, MG

Scanning tunneling spectroscopy measurements were performed on an epitaxial thin film of $La_{0.7}Ca_{0.3}MnO_{3}$ grown on a $NdGaO_{3}$ substrate. The temperature variation of the density of states...

Observation of large low-frequency resistance fluctuations in metallic nanowires: Implications on its stability (2005)

Proceedings of the National Conference on Nanoscience and Technology Part I - National Chemical Laboratory - Pune - 7-8 march 2005 - Foreword (2005)

We have measured the low frequency (1 mHz \leq f \leq 10 Hz) resistance fluctuations in metallic nanowires (diameter 15 nm to 200 nm) in the temperature range 77 K to 400 K. The nanowires were grown...

Electronic transport in nanostructured thin films of perovskite manganite $La_{0.67}Ca_{0.33}Mno_{3}$: role of grain boundaries (2005)

The dawn of 21st century is marked by the birth of a new science Nanoscience and the emanating Nanotechnology. Nanostructures are intermediate in size between molecular and mesoscopic structures...

Paranjape, Mandar A, Shankar, Shantha K, Raychaudhuri, AK

We have prepared nanostructured thin films of $La_{0.67}Ca_{0.33}Mno_{3}$, with an average grain size of around 18 nm, using the chemical solution deposition method. The film has a metal-insulator...

Temperature dependence of the gap in the density of states near the Fermi level in a hole doped manganite (2005)

Kar, Sohini, Mitra, J, Raychaudhuri, AK

In this paper, we report a model-based quantitative analysis of temperature dependent scanning tunneling spectroscopy (STS) data taken on epitaxial thin films of the hole doped manganite...

Proceedings of the National Conference on Nanoscience and Technology - Part II - Foreword (2005)

Collapse of the charge-ordering state at high magnetic fields in the rare-earth manganite $Pr_{0.63}Ca_{0.37}MnO_3$ (2005)

The dawn of 21st century is marked by the birth of a new science Nanoscience and the emanating Nanotechnology. Nanostructures are intermediate in size between molecular and mesoscopic structures...

Nagapriya, KS, Raychaudhuri, AK, Bansal, Bhavtosh, Venkataraman, V, Parashar, Sachin, Rao, CNR

We have investigated the specific heat and resistivity of a single crystal of $Pr_{0.63}Ca_{0.37}MnO_3$ around the charge ordering (CO) transition temperature, $T_{CO}$, in the presence of high...

Point contract spectroscopy and temperature dependence of resistivity of metallic Sodium Tungsten Bronzes - Role of optical phonons (2004)

Gayathri, N, Raychaudhuri, AK

In this paper we report the results of electrical resistivity $(1.5\leq T \leq 300K)$ and point contact spectroscopy (PCS) measurements on single crystals of metallic sodium tungsten bronze with...

Growth of an ordered array of oriented manganite nanowires in alumina templates (2004)

Growth of oriented films of $La_{0.67}Ca_{0.33}MnO_3$ and $La_{0.67}Sr_{0.33}MnO_3$ on $SrTiO_3$ using chemical solution deposition (2004)

We report the growth of oriented nanowires of manganites within the pores of anodic alumina (AAO) templates. The processing of stoichiometric nanowires of $La_{0.67}Sr_{0.33}MnO_3 (LSMO)$ at...

Ghosh, Barnali, Brar, Loveleen K, Jain, Himanshu, Mitra, J, Raychaudhuri, AK

Oriented thin films of $La_{0.67}Sr_{0.33}MnO_3$ and $La_{0.67}Ca_{0.33}MnO_3$ were fabricated on a $SrTiO_3(002)$ single crystal substrate by the chemical solution deposition (CSD) process. The CSD...

Fabrication of ordered array of nanowires of La0.67Ca0.33MnO3 (x=0.33) in alumina templates with enhanced ferromagnetic transition temperature (2004)

Shankar, Shantha K, Kar, Sohini, Raychaudhuri, AK, Subbanna, GN

We report fabrication of array of crystalline nanowires (average diameter of 65 nm) of colossal magnetoresistive oxide La0.67Ca0.33MnO3 (LCMO, x50.33) within anodized alumina templates by filling the...

A set-up for measurement of low frequency conductance fluctuation (noise) using digital signal processing techniques (2004)

Ghosh, Arindam, Kar, Swastik, Bid, Aveek, Raychaudhuri, AK

We describe a set up for measurements of low frequency (1 mHz < f < 20 Hz) conductance fluctuations in a solid conductor. The set-up uses a five probe a.c. measurement technique and extensive digital...

Enhanced ferromagnetic transition temperature in nanocrystalline lanthanum calcium manganese oxide $(La_{0.67}Ca_{0.33}MnO_3)$ (2004)

Shankar, Shantha K, Kar, Sohini, Subbanna, GN, Raychaudhuri, AK

We report a novel, low temperature (450–600 $^oC$) route for the synthesis of highly crystalline and homogeneous nanoparticles of lanthanum calcium manganese oxide $La_{0.67}Ca_{0.33}MnO_3$ (LCMO)....

Fabrication of ordered array of nanowires of La0.67Ca0.33MnO3 (x=0.33) in alumina templates with enhanced ferromagnetic transition temperature (2004)

Shankar, Shantha K, Kar, Sohini, Raychaudhuri, AK, Subbanna, GN

We report fabrication of array of crystalline nanowires (average diameter of 65 nm) of colossal magnetoresistive oxide La0.67Ca0.33MnO3 (LCMO, x50.33) within anodized alumina templates by filling the...

Growth of an ordered array of oriented manganite nanowires in alumina templates (2004)