Probing Spin-Charge Separation in a Tomonaga-Luttinger Liquid
Y. Jompol,1,*
C. J. B. Ford,1
J. P. Griffiths,1
I. Farrer,1
G. A. C. Jones,1
D. Anderson,1
D. A. Ritchie,1
T. W. Silk,2
A. J. Schofield2
In a one-dimensional (1D) system of interacting electrons, excitations
of spin and charge travel at different speeds, according to
the theory of a Tomonaga-Luttinger liquid (TLL) at low energies.
However, the clear observation of this spin-charge separation
is an ongoing challenge experimentally. We have fabricated an
electrostatically gated 1D system in which we observe spin-charge
separation and also the predicted power-law suppression of tunneling
into the 1D system. The spin-charge separation persists even
beyond the low-energy regime where the TLL approximation should
hold. TLL effects should therefore also be important in similar,
but shorter, electrostatically gated wires, where interaction
effects are being studied extensively worldwide.
2 School of Physics and Astronomy, University of Birmingham, Edgbaston, Birmingham B15 2TT, UK.
* To whom correspondence should be addressed. E-mail: yodchay.jompol{at}cantab.net
