M. Roukes - Academia.edu (original) (raw)

Papers by M. Roukes

Research paper thumbnail of Surface physics, low-dimensional systems, and related topics-Magnetotransport measurements on freely suspended two-dimensional electron gases

Research paper thumbnail of Propagation dynamics of individual domain walls in Ga1−xMnxAs microdevices

Physical Review B - PHYS REV B, 2006

We investigated the transport dynamics of individual magnetic domain walls by employing electrica... more We investigated the transport dynamics of individual magnetic domain walls by employing electrical measurements in multiterminal Ga 1−x Mn x As microdevices. Domain wall propagation velocities were deduced from time-of-flight planar Hall measurements between multiple electrical probes of our samples. Domain wall motion induced by both magnetic field and electric currents was systematically investigated. Dependent on the strength of applied in-plane magnetic field, two regimes of domain wall motion, involving thermally assisted flow for low fields and viscous flow for high fields, have been identified. However our data shows no evidence of spin-current induced domain wall motion.

Research paper thumbnail of Direct measurement of the transmission matrix of a mesoscopic conductor

Physical Review Letters, 1992

Research paper thumbnail of Perturbation of magnetostatic modes observed by ferromagnetic resonance force microscopy

Physical Review B, 2006

Magnetostatic modes of yttrium iron garnet ͑YIG͒ films are investigated by ferromagnetic resonanc... more Magnetostatic modes of yttrium iron garnet ͑YIG͒ films are investigated by ferromagnetic resonance force microscopy. A thin-film "probe" magnet at the tip of a compliant cantilever introduces a local inhomogeneity in the internal field of the YIG sample. This influences the shape of the sample's magnetostatic modes, thereby measurably perturbing the strength of the force coupled to the cantilever. We present a theoretical model that explains these observations; it shows that the tip-induced variation of the internal field creates either a local "potential barrier" or "potential well" for the magnetostatic waves. The data and model together indicate that local magnetic imaging of ferromagnets is possible, even in the presence of long-range spin coupling, through the introduction of localized magnetostatic modes predicted to arise from sufficiently strong tip fields.

Research paper thumbnail of Anharmonic effects on a phonon-number measurement of a quantum-mesoscopic-mechanical oscillator

Physical Review A, 2004

ABSTRACT

Research paper thumbnail of Detection of extracellular potentials using a mechanical-based nanosensor

Frontiers in Systems Neuroscience, 2009

Research paper thumbnail of NANO ELECTROMECHANICAL RESONATOR

Research paper thumbnail of Novel Parametric Actuation Scheme in Piezoelectric NEMS

Bulletin of the American …, Jan 1, 2007

Resonant nanoelectromechanical systems (NEMS) are attracting interest in a broad variety of appli... more Resonant nanoelectromechanical systems (NEMS) are attracting interest in a broad variety of applications ranging from ultrasensitive mass and force detectors to quantum limited devices. However, an efficient, fully integrated scheme for actuation and detection remains a challenge. This talk reviews our recent progress in addressing this problem. First, we obtain excellent actuation efficiency using multilayered piezoelectric nanostructures. Second, we employ the piezoelectric properties of these structures for parametric amplification of ...

Research paper thumbnail of Metal Nanowire Resonators

APS March Meeting Abstracts, Mar 1, 2003

Metallic nanowires are a simple, easily fabricated material with applications in nanoelectronic, ... more Metallic nanowires are a simple, easily fabricated material with applications in nanoelectronic, nano-plasmonic and nanomechanical systems. We have developed fabrication techniques to create doubly clamped, suspended beams of metallic nanowires. Through a magnetomotive technique, we have excited and detected the fundamental resonant mode of a platinum nanowire beam. We will present our latest results studying the non-linear behavior of this system, as well as our efforts in frequency tuning and ...

Research paper thumbnail of Ballistic Spin Transport In a Two-Dimensional Electron Gas

Physical Review B, Jan 1, 2000

We explore electrically injected, spin-polarized transport in a ballistic two-dimensional electro... more We explore electrically injected, spin-polarized transport in a ballistic two-dimensional electron gas. We augment the Buttiker-Landauer picture with a simple, but realistic model for spin-selective contacts to describe multimode reservoir-to-reservoir transport of ballistic spin-1/2 particles. Clear and unambiguous signatures of spin transport are established in this regime, for the simplest measurement configuration that demonstrates them directly. These effects originate from spin precession of ballistic carriers; they exhibit a strong depen- dence upon device geometry, and vanish in the diffusive limit. Our results have important implications for prospective ‘‘spin transistor’’ devices.

Research paper thumbnail of Surface physics, low-dimensional systems, and related topics-Magnetotransport measurements on freely suspended two-dimensional electron gases

Research paper thumbnail of Propagation dynamics of individual domain walls in Ga1−xMnxAs microdevices

Physical Review B - PHYS REV B, 2006

We investigated the transport dynamics of individual magnetic domain walls by employing electrica... more We investigated the transport dynamics of individual magnetic domain walls by employing electrical measurements in multiterminal Ga 1−x Mn x As microdevices. Domain wall propagation velocities were deduced from time-of-flight planar Hall measurements between multiple electrical probes of our samples. Domain wall motion induced by both magnetic field and electric currents was systematically investigated. Dependent on the strength of applied in-plane magnetic field, two regimes of domain wall motion, involving thermally assisted flow for low fields and viscous flow for high fields, have been identified. However our data shows no evidence of spin-current induced domain wall motion.

Research paper thumbnail of Direct measurement of the transmission matrix of a mesoscopic conductor

Physical Review Letters, 1992

Research paper thumbnail of Perturbation of magnetostatic modes observed by ferromagnetic resonance force microscopy

Physical Review B, 2006

Magnetostatic modes of yttrium iron garnet ͑YIG͒ films are investigated by ferromagnetic resonanc... more Magnetostatic modes of yttrium iron garnet ͑YIG͒ films are investigated by ferromagnetic resonance force microscopy. A thin-film "probe" magnet at the tip of a compliant cantilever introduces a local inhomogeneity in the internal field of the YIG sample. This influences the shape of the sample's magnetostatic modes, thereby measurably perturbing the strength of the force coupled to the cantilever. We present a theoretical model that explains these observations; it shows that the tip-induced variation of the internal field creates either a local "potential barrier" or "potential well" for the magnetostatic waves. The data and model together indicate that local magnetic imaging of ferromagnets is possible, even in the presence of long-range spin coupling, through the introduction of localized magnetostatic modes predicted to arise from sufficiently strong tip fields.

Research paper thumbnail of Anharmonic effects on a phonon-number measurement of a quantum-mesoscopic-mechanical oscillator

Physical Review A, 2004

ABSTRACT

Research paper thumbnail of Detection of extracellular potentials using a mechanical-based nanosensor

Frontiers in Systems Neuroscience, 2009

Research paper thumbnail of NANO ELECTROMECHANICAL RESONATOR

Research paper thumbnail of Novel Parametric Actuation Scheme in Piezoelectric NEMS

Bulletin of the American …, Jan 1, 2007

Resonant nanoelectromechanical systems (NEMS) are attracting interest in a broad variety of appli... more Resonant nanoelectromechanical systems (NEMS) are attracting interest in a broad variety of applications ranging from ultrasensitive mass and force detectors to quantum limited devices. However, an efficient, fully integrated scheme for actuation and detection remains a challenge. This talk reviews our recent progress in addressing this problem. First, we obtain excellent actuation efficiency using multilayered piezoelectric nanostructures. Second, we employ the piezoelectric properties of these structures for parametric amplification of ...

Research paper thumbnail of Metal Nanowire Resonators

APS March Meeting Abstracts, Mar 1, 2003

Metallic nanowires are a simple, easily fabricated material with applications in nanoelectronic, ... more Metallic nanowires are a simple, easily fabricated material with applications in nanoelectronic, nano-plasmonic and nanomechanical systems. We have developed fabrication techniques to create doubly clamped, suspended beams of metallic nanowires. Through a magnetomotive technique, we have excited and detected the fundamental resonant mode of a platinum nanowire beam. We will present our latest results studying the non-linear behavior of this system, as well as our efforts in frequency tuning and ...

Research paper thumbnail of Ballistic Spin Transport In a Two-Dimensional Electron Gas

Physical Review B, Jan 1, 2000

We explore electrically injected, spin-polarized transport in a ballistic two-dimensional electro... more We explore electrically injected, spin-polarized transport in a ballistic two-dimensional electron gas. We augment the Buttiker-Landauer picture with a simple, but realistic model for spin-selective contacts to describe multimode reservoir-to-reservoir transport of ballistic spin-1/2 particles. Clear and unambiguous signatures of spin transport are established in this regime, for the simplest measurement configuration that demonstrates them directly. These effects originate from spin precession of ballistic carriers; they exhibit a strong depen- dence upon device geometry, and vanish in the diffusive limit. Our results have important implications for prospective ‘‘spin transistor’’ devices.