Self-sensitive torsional microresonators based on a charge-density wave system

V. Ya. Pokrovskii; S. G. Zybtsev

Home/Archive/arXiv

arXiv · 0708.2694

Self-sensitive torsional microresonators based on a charge-density wave system

V. Ya. Pokrovskii·S. G. Zybtsev

View original source ↗Read source document ↗Export metadata ↓

Abstract

Recently, there have been dramatic advances in the miniaturization of electromechanical devices. Most of the micro- and nanoelectromechanical systems (MEMS-NEMS) operate in the resonant modes1. The micron-, and, the more, the submicron-sizes devices, are driven usually by electrostatic forces, as piezoelectric and electromagnetic engines are powerless over this size range. Such engines could play the role of external actuators for the NEMS, being, however, macro devices in their own. Apart from actuation, an objective of NEMS is getting the output signal characterizing the oscillations1, so, actuators sensing their own motion are rather topical (see 2 for example). Not long ago, several works appeared demonstrating high sensitivity of the sizes3,4 and form5 of quasi one-dimensional conductors to the deformations of the charge-density wave (CDW). Here we demonstrate electrically driven torsional resonators based on whiskers of the quasi one-dimensional conductor with CDW, TaS3. The driving force for the torsional deformation is peculiar to the CDW systems and reflects the transmission of the CDW deformation to the crystalline lattice. In comparison with the piezoelectrics, the effect of electric field on the crystal deformation is 3-4 orders of magnitude larger. The resonator is found to provide also a torsion-induced electrical feed-back (output signal) from the oscillations. We discuss the CDW systems as promising elements for NEMS-MEMS.

Explore related subjects

cond-mat.str-el cond-mat.mtrl-sci

Keep this discovery

Explore connections, maps & timelines

BibTeX RIS

V. Ya. Pokrovskii, S. G. Zybtsev. 2007-08-20. Self-sensitive torsional microresonators based on a charge-density wave system. https://arxiv.org/abs/0708.2694

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Tensor Network Representations for Intrinsically Mixed-State Topological Orders

Tensor networks are an efficient platform for representing topological states of matter as well as computing both physical observables and information-theoretic quantities. We present a general protocol to construct tensor network representations for intrinsically mixed-state topological phases. Such phases naturally emerge in noisy long-range entangled quantum systems, and exhibit nontrivial topological phenomena without pure-state counterparts. The method exploits the isomorphism between anyon decoherence in the physical Hilbert space and anyon condensation in the corresponding Choi space. The protocol is applicable to a broad class of systems arising from decoherence of pure-state topological phases, where the incoherent noise creates excitations in the Choi space that have trivial monodromy with all excitations. Representative examples at renormalization group fixed points include $m^a e^b$ decoherence in the $\Z_N$ toric code, decohered non-Abelian quantum double of $S_3$ as well as pure $Z$/$X$ decoherence of arbitrary CSS codes. Another notable example is that of the mixed-state chiral semion, whose tensor network representation has no pure-state analogue. We then generalize the formalism beyond RG fixed points and, as an example, examine the decoherence transition in a $\mathbb{Z}_3$ toric code channel that suffers from sign problem when mapped to a statistical mechanical model. Together, these results establish tensor networks as a natural platform for analyzing noisy intrinsically mixed-state topological matter.

cond-mat.str-el↗

arXiv2026

Frustration from Localized Zhang-Rice States: A Unified Theory of Doping-Driven Magnetic Transitions in Cuprates

The microscopic mechanism by which doped holes disrupt the antiferromagnetic (AFM) order is one of the fundamental questions in cuprates. In this work, we propose a unified microscopic theory in which doped holes form spatially localized Zhang-Rice singlets which actively mediate emergent spin exchange. Rather than acting as simple non-magnetic vacancies, these localized states introduce emergent next-nearest $J_2$ and third-nearest $J_3$ neighbor superexchanges. This dopant-induced exchange pathway generates significant magnetic frustration, naturally explaining the rapid collapse of the Néel AFM order and the emergence of a spin-glass phase on the hole-doped side. In contrast, electron doping primarily leads to spin dilution, allowing AFM order to persist to substantially higher doping levels, consistent with the experimentally observed electron-hole asymmetry. Our findings provide a unified microscopic framework for understanding doping-driven magnetic transitions in lightly doped cuprates.

cond-mat.str-el↗

arXiv2026

Correlated States in Quantum Dot Clusters Coupled to a Common Superconductor

We study an effective model of regular quantum dot clusters coupled to a common superconductor. By applying a canonical transformation, we map the system onto a particle-number-conserving representation, enabling an efficient treatment with standard fermionic neural-network quantum-state variational Monte Carlo methods. We show that the excitation gap can close under a particular high-symmetry condition, which, in finite non-interacting systems, corresponds to crossings between singlet ground states of different character. At this high-symmetry condition the model can be mapped to a standard Hubbard model in grand-canonical ensemble with fixed chemical potential away from half-filling. Combining exact methods, density matrix renormalization group, and neural quantum-state variational Monte Carlo calculations, we identify three distinct interacting regimes: a trivial superconducting singlet phase, a strongly correlated regime related to an effective Heisenberg model, and a critical intermediate regime with qualitatively different behavior in one and two dimensions. In one-dimensional systems, the intermediate regime exhibits a sequence of singlet-doublet transitions and becomes gapless in the thermodynamic limit even for finite Coulomb interaction. In two-dimensional clusters, we find robust triplet ground states. These results connect the physics of superconducting nanostructures with correlated lattice models and show that standard fermionic neural quantum states can capture the relevant interacting regimes.

cond-mat.str-el↗