Publications de Harry Joseph Trodahl

Phase transitions associated with competing order parameters in compressively strained SrTiO3 thin films

Alexander Tagantsev, Harry Joseph Trodahl

(100)-epitaxial SrTiO3 thin films having biaxial compressive strains up to -1.60% were grown on lattice mismatched substrates. Two phase transitions induced by the coupled instabilities (antiferrodistortive and ferroelectric) in SrTiO3 were revealed in a c ...

Amer Physical Soc2015

Elastic, dielectric, and piezoelectric anomalies and Raman spectroscopy of 0.5Ba(Ti0.8Zr0.2)O3-0.5(Ba0.7Ca0.3)TiO3

Dragan Damjanovic, Harry Joseph Trodahl, Alberto Biancoli, Leili Batooli, Amirhossein Vahabzadeh

The solid solution 0.5Ba(Ti0.8Zr0.2)O-3-0.5(Ba0.7Ca0.3)TiO3 (BCZT) is a promising lead-free piezoelectric material with exceptionally high piezoelectric coefficients. The strong response is related to structural instabilities close to ambient temperature. ...

American Institute of Physics2012

Magnetic domain wall propagation under ferroelectric control

Nava Setter, Igor Stolichnov, Harry Joseph Trodahl, Sebastian Riester, Evgeny Mikheev

Control of magnetic domain walls (DWs) and their propagation is among the most promising development directions for future information-storage devices. The well-established tools for such manipulation are the spin-torque transfer from electrical currents a ...

American Physical Society2012

Nearest-neighbor Mn antiferromagnetic exchange in Ga(1-x)MnxN

Simon Granville, Harry Joseph Trodahl

We analyze the magnetic behavior of well-characterized, precipitate-free Ga1-xMnxN thin films containing Mn at higher levels than previously attained; up to x=0.36. This level is above the percolation threshold x(c) for nearest-neighbor cations, such that ...

2010

Toward a low-voltage multiferroic transistor: Magnetic (Ga,Mn)As under ferroelectric control

Nava Setter, Igor Stolichnov, Harry Joseph Trodahl, Sebastian Riester

The persistent field effect control of ferromagnetism in a diluted magnetic semiconductor by low-voltage polarizing pulses is demonstrated in a ferroelectric gate field effect transistor configuration. The Curie temperature of the (Ga,Mn)As channel is unam ...

AIP American Institute of Physics2009

Vibrational properties of rare-earth nitrides: Raman spectra and theory

Simon Granville, Harry Joseph Trodahl

Raman spectra are presented for the rare-earth nitrides SmN, GdN, DyN, ErN, and LuN measured with 633 and 514 nm excitation wavelengths and at temperatures above and below the Curie temperature. Frozen-phonon calculations are presented for the phonons at G ...

2009

Control of Ferromagnetism in a (Ga,Mn)As - Based Multiferroic System via a Ferroelectric Gate

Nava Setter, Igor Stolichnov, Harry Joseph Trodahl, Sebastian Riester

We report the implementation of a ferroelectric gate field effect transistor (FeFET) with a ferromagnetic (Ga,Mn)As conducting channel. The Curie temperature T-C in the channel is modulated by non-volatile poling of the gate. The ferroelectric state, and t ...

Amer Inst Physics, 2 Huntington Quadrangle, Ste 1No1 D, Melville, Ny 11747-4501 Usa2009

Near-zero-moment ferromagnetism in the semiconductor SmN

Simon Granville, Harry Joseph Trodahl

The magnetic behavior of SmN has been investigated in stoichiometric polycrystalline films. All samples show ferromagnetic order with Curie temperature (T-C) of 27 3 K, evidenced by the occurrence of hysteresis below T-C. The ferromagnetic state is charact ...

2008

Raman spectroscopy of (K,Na)NbO3 and (K,Na)(1-x)LixNbO3

Nava Setter, Dragan Damjanovic, Naama Klein, Harry Joseph Trodahl

We report Raman spectroscopy in all four phases of a (K0.5+delta Na0.5-delta)NbO3 (delta similar to 0.03) crystal and ((K0.5+delta Na0.5-delta)(1-x)Li-x)NbO3 for x=0.02 and 0.03. The phase transitions in the Li-free crystal are homogeneous and hysteretic, ...

AIP American Institute of Physics2008

Ferroelectric control of ferromagnetism in diluted magnetic semiconductors

Nava Setter, Igor Stolichnov, Harry Joseph Trodahl, Sebastian Riester

Ieee Service Center, 445 Hoes Lane, Po Box 1331, Piscataway, Nj 08855-1331 Usa2008