Low-temperature magnetic ordering in SrEr$_2$O$_4$ (2008)
Petrenko, O. A., Balakrishnan, G., Wilson, N. R., De Brion, S., Suard, E., Chapon, L. C.
SrEr$_2$O$_4$ has been characterised by low-temperature powder neutron diffraction, as well as single crystal specific heat and magnetisation measurements. Magnetisation measurements show that the...
Tung, L. D., Ivanov, A., Schefer, J., Lees, M. R., Balakrishnan, G., Paul, D. McK
We report the results of magnetization, heat capacity and neutron scattering studies of LaVO3 single crystals. From the neutron diffraction studies, it was found that the compound is magnetically...
Electronic texture of the thermoelectric oxide Na0.75CoO2 (2008)
De Vaulx, C., Mayaffre, H., Berthier, C., Horvatic, M., Simonet, V., ...
From 59Co and 23Na NMR, we demonstrate the impact of the Na+ vacancy ordering on the cobalt electronic states in Na0.75CoO2: at long time scales, there is neither a disproportionation into 75 % Co3+...
Elliptical hole pockets in the Fermi surfaces of unhydrated and hydrated sodium cobalt oxides (2007)
Laverock, J., Dugdale, S. B., Duffy, J. A., Wooldridge, J., Balakrishnan, G., Lees, M. R., ...
The surprise discovery of superconductivity below 5K in sodium cobalt oxides when hydrated with water has caught the attention of experimentalists and theorists alike. Most explanations for its...
Tung, L D, Lees, M R, Balakrishnan, G, Paul, D McK
We report on a study of various RVO3 single-crystal samples (R = La, Nd, Sm, Gd, Er and Y) which show temperature-induced magnetization reversal. For compounds with lighter rare-earths (R = La, Nd...
Wearable Real-Time Stereo Vision for the Visually Impaired (2007)
G. Balakrishnan, G. Sainarayanan, R. Nagarajan, Sazali Yaacob
Magnetocaloric effect in pyrochlore antiferromagnet Gd2Ti2O7 (2006)
Sosin, S. S., Prozorova, L. A., Smirnov, A. I., Golov, A. I., Berkutov, I. B., Petrenko, O. A., ...
An adiabatic demagnetization process is studied in Gd2Ti2O7, a geometrically frustrated antiferromagnet on a pyrochlore lattice. In contrast to conventional paramagnetic salts, this compound can...
Magnetic excitations in the Kagome staircase compounds (2006)
Wilson, N. R., Petrenko, O. A., Balakrishnan, G., Manuel, P., Fak, B.
Inelastic neutron scattering measurements have been performed on single crystal samples of Co3V2O8 and Ni3V2O8. The magnetic system in these compounds is believed to be frustrated, as the magnetic...
Magnetic phase diagrams of the Kagome staircase compounds Co3V2O8 and Ni3V2O8 (2006)
Wilson, N. R., Petrenko, O. A., Balakrishnan, G.
An extensive low temperature magnetisation study of high quality single crystals of the Kagome staircase compounds Ni3V2O8 and Co3V2O8 has been performed, and the H-T phase diagrams have been...
Intraplanar Magnetic Excitations in Na0.5CoO2: An Inelastic Neutron Study (2006)
Wooldridge, J., Balakrishnan, G., Paul, D. McK., Frost, C., Bourges, P., Lees, M. R.
Inelastic neutron scattering measurements mapping the in-plane magnetic interactions of Na0.5CoO2 reveal dispersive excitations at points above an energy gap Eg = 11.5(5) meV at the superstructural...
Magnetic resonance in a pyrochlore antiferromagnet Gd2Ti2O7 (2006)
Sosin, S. S., Smirnov, A. I., Prozorova, L. A., Balakrishnan, G., Zhitomirsky, M. E.
Electron spin resonance study of frustrated pyrochlore Gd2Ti2O7 is performed in a wide frequency band for a temperature range 0.4-30 K, which covers paramagnetic and magnetically ordered phases. The...
Sarkar, S, Tomy, C V, Thakur, A D, Balakrishnan, G, Paul, D McK, Ramakrishnan, S, ...
We have studied metastability effects pertaining to the peak effect (PE) in critical current density ($J_c$) via isofield scans in ac susceptibility measurements in a weakly pinned single crystal of...
Critical points in the Bragg glass phase of a weakly pinned crystal of Ca$_3$Rh$_4$Sn$_{13}$ (2005)
Sarkar, S., Thakur, A. D., Tomy, C. V., Balakrishnan, G., Paul, D. McK., Ramakrishnan, S., ...
New experimental data are presented on the scan rate dependence of the magnetization hysteresis width $\Delta M(H)$ ($\propto$ critical current density $J_c(H)$) in isothermal $M-H$ scans in a weakly...
Wooldridge, J., Paul, D. McK., Balakrishnan, G., Lees, M. R.
We have measured the magnetic field (H
Field-induced magnetic phase transitions in a GdSi single crystal (2005)
Tung, L.D., Lees, M., Balakrishnan, G., Paul, D.M., Schobinger-Papamantellos, P., Tegus, O., ...
Revised magnetic properties of CuFeO2 - a case of mistaken identity (2005)
Petrenko, O. A., Lees, M. R., Balakrishnan, G., De Brion, S., Chouteau, G.
Low-energy excitations in La1.2Sr1.8Mn2O7 investigated by ellipsometry (2005)
Mercier, O. R., Buckley, R. G., Trodahl, H. J., Bernhard, C., Balakrishnan, G.
Single crystals of the anisotropic Kagome staircase compounds Ni3V2O8 and Co3V2O8 (2004)
Balakrishnan, G., Petrenko, O. A., Lees, M. R., Paul, D. McK.
Compounds with a Kagome type lattice are known to exhibit magnetic frustration. Large single crystals of two compounds Ni3V2O8 and Co3V2O8, which are variants of a Kagome net lattice, have been grown...
Investigation of the Spin Density Wave in NaxCoO2 (2004)
Wooldridge, J., Paul, D. McK, Balakrishnan, G., Lees, M. R.
Magnetic susceptibility, transport and heat capacity measurements of single crystal NaxCoO2 (x=0.71) are reported. A transition to a spin density wave (SDW) state at Tmag = 22 K is observable in all...
Neutron Scattering Investigation of the Spin Ice State in Dy2Ti2O7 (2004)
Fennell, T., Petrenko, O. A., Fak, B., Bramwell, S. T., Enjalran, M., Yavors'kii, T., ...
Dy2Ti2O7 has been advanced as an ideal spin ice. We present a neutron scattering investigation of a sample of 162Dy2Ti2O7. The scattering intensity has been mapped in zero applied field in the hhl...
Magnetocaloric effect in pyrochlore antiferromagnet Gd2Ti2O7 (2004)
Sosin, S. S., Prozorova, L. A., Smirnov, A. I., Golov, A. I., Berkutov, I. B., Petrenko, O. A., ...
An adiabatic demagnetization process is studied in Gd2Ti2O7, a geometrically frustrated antiferromagnet on a pyrochlore lattice. In contrast to conventional paramagnetic salts, this compound can...
Neutron scattering investigation of the spin ice state in Dy2Ti2O7 (2004)
Fennell, T, Petrenko, O A, Fak, B, Bramwell, S T, Enjalran, M, Yavors'kii, T, ...
Dy2Ti2O7 has been advanced as an ideal spin ice material. We present a neutron scattering investigation of a single-crystal sample of (Dy2Ti2O7)-Dy-162. The scattering intensity has been mapped in...
Magnetic phase diagram of the antiferromagnetic pyrochlore Gd2Ti2O7 (2003)
Petrenko, O. A., Lees, M. R., Balakrishnan, G., Paul, D. McK.
Gd2Ti2O7 is a highly frustrated antiferromagnet on a pyrochlore lattice, where apart from the Heisenberg exchange the spins also interact via dipole-dipole forces. We report on low-temperature...
Oxygen Moment Formation and Canting in Li2CuO2 (2003)
Chung, E. M. L., McIntyre, G. J., Paul, D. McK., Balakrishnan, G., Lees, M. R.
The possibilities of oxygen moment formation and canting in the quasi-1D cuprate Li2CuO2 are investigated using single crystal neutron diffraction at 2 K. The observed magnetic intensities could not...
The role of electronic correlations on the phonon modes of MnO and NiO (2003)
Chung, E. M. L., Paul, D. McK., Balakrishnan, G., Lees, M. R., Ivanov, A., Yethiraj, M.
The possibility of magnetic-order induced phonon anisotropy in single crystals of MnO and NiO is investigated using inelastic neutron scattering. Below Tn both compounds exhibit a splitting in their...
Growth of large single crystals of Rare Earth Hexaborides (2003)
Balakrishnan, G., Lees, M. R., Paul, D. McK.
Single crystal growth of several rare earth hexaborides has been carried out by the floating zone technique. A high power Xenon arc lamp image furnace was used for the crystal growth. Large high...
Anisotropic low field behavior and the observation of flux jumps in CeCoIn5 (2003)
Majumdar, S., Lees, M. R., Balakrishnan, G., Paul, D. McK
The magnetic behavior of the heavy fermion superconductor CeCoIn5 has been investigated. The low field magnetization data show flux jumps in the mixed state of the superconducting phase in a...
Er2Ti2O7: Evidence of quantum order by disorder in a frustrated antiferromagnet (2003)
Champion, J D M, Harris, M J, Holdsworth, P C W, Wills, A S, Balakrishnan, G, Bramwell, S T, ...
Raman scattering study of Nd1-xSrxMnO3 (x=0.3, 0.5) (2003)
Lemmens, P., Güntherodt, G., Pattabiraman, M., Rangarajan, G., Gnezdilov, V. P., ...
Comment on "Short-range magnetic interactions in the spin-ice compound Ho2Ti2O7" (2002)
Petrenko, O. A., Lees, M. R., Balakrishnan, G.
In their recent communication (Phys. Rev. B 64, 060406(R) (2001)) Cornelius and Gardner have reported the results of magnetization and susceptibility studies on single crystals of the pyrochlore...
Pressure Induced Change in the Magnetic Modulation of CeRhIn5 (2002)
Majumdar, S., Balakrishnan, G., Lees, M. R., Paul, D. McK, McIntyre, G. J.
We report the results of a high pressure neutron diffraction study of the heavy fermion compound CeRhIn5 down to 1.8 K. CeRhIn5 is known to order magnetically below 3.8 K with an incommensurate...
Microwave properties of Nd_0.5Sr_0.5MnO_3: a key role of the (x^2-y^2)-orbital effects (2002)
Zvyagin, S., Angerhofer, A., Kamenev, K. V., Balakrishnan, G., Paul, D. McK.
Transmittance of the colossal magnetoresistive compound Nd_0.5Sr_0.5MnO_3 showing metal-insulator phase transition has been studied by means of the submm- and mm-wavelength band spectroscopy. An...
Field-induced partial order in the spin ice dysprosium titanate (2002)
Fennell, T, Petrenko, O A, Balakrishnan, G, Bramwell, S T, Champion, J D M, Fak, B, ...
Zwier, J.M., Brouwer, A.M., Keszthelyi, T., Balakrishnan, G., Offersgaard, J.F., Wilbrandt, R., ...
The radical cation of 1,3,6,8-tetraazatricyclo [4.4.1.1(3,8)]dodecane (TTD) has been studied using magnetic resonance and optical spectroscopic methods and computational techniques. With the help of...
Er2Ti2O7: Evidence of Order by Disorder in a Frustrated Antiferromagnet (2001)
Champion, J. D. M., Harris, M. J., Holdsworth, P. C. W., Wills, A. S., Balakrishnan, G., Bramwell, S. T., ...
Er_2Ti_2O_7 has been suggested to be a realization of the frustrated < 111 > XY pyrochlore lattice antiferromagnet, for which theory predicts fluctuation-induced symmetry breaking in a highly...
Field Induced Partial Order in the Spin-Ice Dysprosium Titanate (2001)
Fennell, T., Petrenko, O. A., Balakrishnan, G., Bramwell, S. T., Champion, J. D. M., Fak, B., ...
Neutron scattering has been used to investigate the magnetic correlations in the the spin ice material dysprosium titanate, Dy2Ti2O7. An isotopically enriched sample was used to minimise neutron...
Pal, D., Sarkar, S., Tulapurkar, A., Ramakrishnan, S., Grover, A. K., Ravikumar, G., ...
A comparison of the history effects in weakly pinned single crystals of a high $T_c$ YBa$_2$Cu$_3$O$_{7 - \delta}$ (for H $\parallel$ c) and a low $T_c$ Ca$_3$Rh$_4$Sn$_{13}$, which show anomalous...
An Agent-Based Netcentric Framework For Multidisciplinary Problem Solving Environments (MPSE) (2001)
S. Markus, E. N. Houstis, A. C. Catlin, J. R. Rice, P. Tsompanopoulou, E. Vavalis, ...
this document, we describe the initial design of a generic MPSE framework based on a network of computational agents assuming a net-centric run-time support environment. Moreover, we present the...
Network-based Scientific Computing (2001)
Houstis, E.N., Balakrishnan, G., Catlin, A., Dhanjani, N., Lalis, S., Stamatogiannakis, M., ...
Network-based Scientific Computing, The Architecture of Scientific Software (2001)
Houstis, E.N., Balakrishnan, G., Catlin, A., Dhanjani, N., Lalis, S., Stamatogiannakis, M., ...
Pressure effects on the magnetic and structural properties of layered manganites (2001)
Kamenev, K V, Marshall, W G, Lees, M R, Paul, D M, Balakrishnan, G, Tissen, V G, ...
High Magnetic Field Behaviour of the Triangular Lattice Antiferromagnet, CuFeO_2 (2000)
Petrenko, O. A., Balakrishnan, G., Lees, M. R., Paul, D. McK, Hoser, A.
The high magnetic field behaviour of the triangular lattice antiferromagnet CuFeO_2 is studied using single crystal neutron diffraction measurements in a field of up to 14.5 T and also by...
Pressure tuning of magnetic interactions in layered (La0.6Nd0.4)1.2Sr1.8Mn2O7 Manganite (2000)
Kamenev, K V, Lees, M R, Balakrishnan, G, Paul, D McK, Marshall, W G, Tissen, V G, ...
The radical cation and lowest Rydberg states of 1,4-diaza[2.2.2]bicyclooctane (DABCO). (2000)
Balakrishnan, G., Keszthelyi, T., Wilbrandt, R., Zwier, J.M., Brouwer, A.M., Buma, W.J.
The radical cation and the two lowest excited singlet Rydberg states of DABCO (1,4-diazabicyclo[2.2.2]octane) are studied. Experimentally, the radical cation of DABCO is generated by either laser...
Allodi, G., De Renzi, R., Solzi, M., Kamenev, K., Balakrishnan, G., Pieper, M. W.
The antiferromagnetic manganite Pr$_{0.5}$Sr$_{0.5}$MnO$_3$ was investigated at low temperature by means of magnetometry and $^{55}$Mn NMR. A field-induced transition to a ferromagnetic state is...
Sarkar, S., Pal, D., Banerjee, S. S., Ramakrishnan, S., Grover, A. K., Tomy, C. V., ...
The Peak Effect (PE) regime in a single crystal of Ca$_3$Rh$_4$Sn$_{13}$ has been investigated in detail via ac susceptibility as well as dc magnetization measurements. The PE region comprises two...
Intermolecular hydrogen abstraction reaction mechanisms in photoexcited ketones have traditionally been studied using time resolved absorption spectroscopy. Another approach is presented involving...
Intermolecular hydrogen abstraction reaction mechanisms in photoexcited ketones have traditionally been studied using time resolved absorption spectroscopy. Another approach is presented involving...
The effect of magnetic ordering on the crystal field levels of ErNi2b2C (1995)
Gardner, J S, Tomy, C V, Afalfiz, L, Balakrishnan, G, McK Paul, D, Rainford, B D, ...
Heat capacity of the crystal field effects in the ErNi2B2C compound (1994)
Afalfiz, L, Tomy, C V, Gardner, J S, Goremychkin, E A, Eccleston, R S, Balakrishnan, G, ...
Vibrational anomalies in the superconducting compound La1.85Ba0.15CuO4 (1987)
Balakrishnan, G, Bernhoeft, N R, Bowden, Z A, McK Paul, D, Taylor, A D
Intracranial pressure monitoring in a group of critically ill children.
Balakrishnan, G, Skeoch, C H, Stephenson, J B, McWilliam, R C, Hallworth, D, Sinclair, J F
Enhanced thrombin generation in patients receiving intensive care.
Balakrishnan, G, Brownlie, J, Webber, R, Gibson, B
Thrombin-antithrombin III complex (TAT) concentration was measured in 27 control and 155 intensive care patients to (a) establish normal reference ranges, (b) measure thrombin generation in...
Prospective evaluation of the Paediatric Risk of Mortality (PRISM) score.
Balakrishnan, G, Aitchison, T, Hallworth, D, Morton, N S
The performance of the admission day Paediatric Risk of Mortality (PRISM) score for outcome prediction was assessed prospectively in 270 consecutive admissions, aged 3 days to 18.6 years, to a...