Dopant-bound spinons in Cu
 
 1 −
 x
 
 Zn
 
 x
 
 GeO
 3

Els, G.; Uhrig, Götz S.; Lemmens, P.; Vonberg, H.; Loosdrecht, P.H.M. van; Güntherodt, G.; Fujita, Osamu; Akimitsu, Jun; Dhalenne, G.; Revcolevschi, A.

doi:10.1209/epl/i1998-00382-3

Cited by 19 publications

(27 citation statements)

References 38 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Soliton-assisted one-magnon excitation was recently proposed as the origin of the 17 cm Ϫ1 peak in the dimerized phase [18] and was studied independently in some theoretical detail by Els et al for Zndoped CuGeO 3 [25]. Consider the Fleury-Loudon type operator for inelastic light scattering based on the exchange scattering mechanism [26,27] …”

mentioning

confidence: 99%

Low-energy magnetic excitations in the dimerized and incommensurate phase of CuGeO3

Loa

Gronemeyer

Thomsen

et al. 1999

Solid State Communications

View full text Add to dashboard Cite

Low-energy magnetic excitations in the dimerized (D) and incommensurate (I) phase of CuGeO 3 were studied by Raman spectroscopy. Based on temperature and magnetic field dependent experiments on pure and Si-doped samples the Raman peak at 17 cm Ϫ1 for T 2 K in the D-phase is attributed to a soliton-assisted one-magnon excitation. We further present a Ramanstudy of the low-energy spin dynamics of a spin-Peierls system in the incommensurate phase. The magnetic field induced transition between D-and I-phase of CuGeO 3 (B c տ 12.5 T) is characterized by the appearance of an intense new low-energy mode. For the incommensurate phase a finite zone-center excitation gap of D 2.3^0.2 cm Ϫ1 is deduced. ᭧

show abstract

mentioning

confidence: 99%

Low-energy magnetic excitations in the dimerized and incommensurate phase of CuGeO3

Loa

Gronemeyer

Thomsen

et al. 1999

Solid State Communications

View full text Add to dashboard Cite

show abstract

mentioning

confidence: 82%

“…(12) shows that the magnetic component of a given Raman peak increases when its position shifts from a phonon frequency. The lower energy eigenvalue of Fig(2) starts being a trapped phonons for ω ∆ < 1 and transmutes in a magneto-phonon in the opposite limit where the real material lives.…”

Section: Kmentioning

confidence: 99%

“…Direct magnon process could not be seen in the optical response due to spin conservation. Soliton assisted one magnon excitation was recently been proposed as the origin of this peak [2] in similarity with the situation in the presence of non-magnetic impurities [12].This approach is based on the image of the soliton as an isolated spin in the externally dimerized chain so that an adiabatic approximation is supposed. We will show that this state in fact disappears when the dynamics of the phonons is included .…”

mentioning

confidence: 99%

“…The bound state has the same total spin as the soliton. Then, it is an optical active mode and it is the analogue in our formalism of the so called soliton assisted magnon process founded in the strong dimerization limit [12].…”

mentioning

confidence: 99%

See 2 more Smart Citations

Mixing of magnetic and phononic excitations in incommensurate spin-Peierls systems

Dobry

Ibaceta

2001

Phys. Rev. B

View full text Add to dashboard Cite

We analyze the excitation spectra of a spin-phonon coupled chain in the presence of a soliton. This is taken as a microscopic model of a Spin-Peierls material placed in a high magnetic field. We show, by using a semiclassical approximation in the bosonized representation of the spins that a trapped magnetic state obtained in the adiabatic approximation is destroyed by dynamical phonons. Low energy states are phonons trapped by the soliton. When the magnetic gap is smaller than the phonon frequencies the only low energy state is a mixed magneto-phonon state with the energy of the gap. We emphasize that our results are relevant for the Raman spectra of the inorganic Spin-Peierls material CuGeO3.The discovery in 1993 by Hase et al [1] of the first inorganic Spin-Peierls compound CuGeO 3 has opened the possibility of study the physics of this collective phenomena in a deep way. Several experimental proves have given an exhaustive information about the excitation spectra of this system and its evolution with an applied magnetic field. The effect of non-magnetic impurities has been investigated also.Theoretical studies have focused on simplified magnetic model. The excitation spectra in the low temperature phase have been analyzed using a dimerized and frustrated Heisenberg chain as a minimal model for this material [3][4][5]. The logic underlying these studies are: the competition between magnetic and elastic energies resolves in the low temperature phase in the dimerization of the lattice. Once this process takes place, phononic and magnetic excitation completely decouple and the magnetic excitations are the same as the chemical dimerized system. This point of view is based on an adiabatic approximation supposing that the energy scale of the magnetic process are high enough respect to the phononic ones. As it has been recently emphasized [6], this relation is not fulfilled for CuGeO 3 where the phonons relevant for the dimerization process are about one order of magnitude more energetic than the magnetic gap. The adiabatic approximation is questionable for this system. An antiadiabatic approach has been developed. The frustrated interaction arises, in this context, from the integration of the in-chain phonons and the explicit dimerization from the interchain interaction treated in a mean field approximation [7]. The same frustrated-dimerized Hamiltonian is therefore obtained but with a reinterpretation of the parameters. What is clearly missed in these studies is a general understanding on how spin and phonons mix as elementary excitation and how the spectra of Spin-Peierls systems is built as a result of this mixing. Some recent numerical results have partially addressed this question [8].In this paper, we analyze the excitation spectra of onedimensional spin-phonon system by semiclassical techniques on the bosonized representation of the spins subsystem. We focus on the properties of this system in a high magnetic field. In the dimerized phase the system is in a singlet ground state. Coupling with a magnetic field...

show abstract

Optical Techniques for Systems with Competing Interactions

Lemmens

2010

Introduction to Frustrated Magnetism

View full text Add to dashboard Cite

Dopant-bound spinons in Cu _{1 −
x} Zn _x GeO ₃

Cited by 19 publications

References 38 publications

Low-energy magnetic excitations in the dimerized and incommensurate phase of CuGeO3

Low-energy magnetic excitations in the dimerized and incommensurate phase of CuGeO3

Mixing of magnetic and phononic excitations in incommensurate spin-Peierls systems

Optical Techniques for Systems with Competing Interactions

Contact Info

Product

Resources

About

Dopant-bound spinons in Cu 1 − x Zn x GeO 3

Cited by 19 publications

References 38 publications

Low-energy magnetic excitations in the dimerized and incommensurate phase of CuGeO3

Low-energy magnetic excitations in the dimerized and incommensurate phase of CuGeO3

Mixing of magnetic and phononic excitations in incommensurate spin-Peierls systems

Optical Techniques for Systems with Competing Interactions

Contact Info

Product

Resources

About

Dopant-bound spinons in Cu _{1 −
x} Zn _x GeO ₃