12,851 research outputs found
Magnetic order and moment distribution in doped spin-chain systems
We consider the effect of doping on the magnetic order in quasi
one-dimensional (1D) antiferromagnets. First the detailed magnetic response of
finite spin-1/2 chains in the presence of a staggered field is determined,
which by itself shows an interesting crossover as function of length and field
strength. We can then understand the ordering by including an effective
coupling between the chains, which results in a Neel ordered phase at low
temperatures, but with a broad distribution of magnetic moments that has to be
determined self-consistently.Comment: 2 pages, 1 figure. Latest pdf-file is available at
http://www.physik.uni-kl.de/eggert/papers/magorder.pd
Reply to the "Comment on 'Phase diagram of an impurity in the spin-1/2 chain: two channel Kondo effect versus Curie law'"
In a comment by A.A. Zvyagin the phase diagram in our Letter [Phys. Rev.
Lett. 86, 516 (2001)] was critisized of being incomplete and a new fixed point
was suggested. We show that this point is in fact not a fixed point and that
the phase diagram is correct as presented.Comment: Reply to a comment by A.A. Zvyagin. 1 page, 1 figure. The latest
version in PDF format is available from
http://fy.chalmers.se/~eggert/papers/reply.pd
Recursive Method for the Density of States in One Dimension
We derive a powerful yet simple method for analyzing the local density of
states in gapless one dimensional fermionic systems, including extensions such
as momentum dependent interaction parameters and hard-wall boundaries. We study
the crossover of the local DOS from individual density waves to the well-known
asymptotic powerlaws and identify characteristic signs of spin charge
separation in possible STM experiments. For semi-infinite systems a closed
analytic expression is found in terms of hypergeometric functions.Comment: 5 pages and 3 figures. The latest version can be found at
http://www.physik.uni-kl.de/eggert/papers/index.htm
A two-channel Kondo impurity in the spin-1/2 chain: Consequences for Knight shift experiments
A magnetic impurity in the spin-1/2 chain is a simple realization of the
two-channel Kondo problem since the field theoretical descriptions in the
spin-sector are identical. The correlation functions near the impurity can be
calculated. Using a modified version of the numerical transfer matrix DMRG, we
are able to accurately determine local properties close to the impurity in the
thermodynamic limit. The local susceptibilities (Knight-shifts) show an
interesting behavior in a large range around the impurities. We are able to
make quantitative experimental predictions which would allow to observe
two-channel Kondo physics for the first time directly by doping of spin-1/2
chain compounds.Comment: 2 pages in revtex format including 2 embedded figures (using epsf
Violence and Silence: The Prison Rape Elimination Act and Beyond
Connecting the #MeToo movement to sexual abuse in prisons, this paper analyzes the flaws of the Prison Rape Elimination Act of 2003. Examining the genesis behind PREA, the lack of enforcement and accountability, and the remaining unresolved issues, I argue that the law fails to meaningfully combat the pervasive and multifaceted problem of sexual abuse in US prisons. The racist, sexist, and homophobic ideologies that gave rise to PREA, as well as its focus on prison efficiency rather than prisoners’ lives, only serve to further entrench harmful biases within United States prisons and broader society
International Percussions of Direct Taxes
This paper anlyzes the impact of tax competition between two countries of un- equal per-capita capital endownments on tax rates and efficiency when distorting wage, residence-based and source-based capital taxes (or any combination of two instruments) are available for governments. The national welfare costs and benefits of tax rate variations are shown to be ambiguous in the asymmetric Nash equilibrium due to the existence of tax base and terms of trade effects. Moreover, numerical simulation results indicate that non-cooperative equilibria in Nash strategies are inefficient from an international perspective, even if residence-based capital taxes are in the set of tax instruments available to fiscal authorities.
International Percussions of Direct Taxes
This peper anlyzes the impact of tax competition between two countries of un- equal per-capita capital endownments on tax rates and efficiency when distorting wage, residence-based and source-based capital taxes (or any combination of two instruments) are available for governments. The national welfare costs and benefits of tax rate varia- tions are shown to be ambiguous in the asymmetric Nash equilibrium due to the existence of tax base and terms of trade effects. Moreover, numerical simulation results indicate that non-cooperative equilibria in Nash strategies are inefficient from an international perspective, even if residence-based capital taxes are in the set of tax instruments available to fiscal authorities.
Company tax coordination cum tax rate competition in the European Union
This paper reviews the recent theoretical literature that analyses the European Union's policy to eliminate preferential corporate tax regimes and the proposal to introduce a consolidated EU tax base with formula apportionment for the taxation of multinational firms. Since neither proposal includes a harmonisation of corporate tax rates, a core issue is how tax competition between member states will be affected by these partial coordination measures. The conclusions from our review are supportive of the EU's ban on preferential tax regimes, but the economic incentive effects of a switch to formula apportionment are found to be ambiguous
Fisheries Economics and 20 Years with Marine Resource Economics: A Citation Analysis
Abstract This paper reviews the impact of articles published in the Marine Resource Economics (MRE) and within the field of fisheries economics in general over the period 1954–2004. Specific attention is given to the years 1984–2004, which is the period that MRE has been published. The degree of influence is assessed using citation analysis. I present the most cited papers in MRE, the top ten all time cited fisheries economics papers, and the most cited papers during each decade over the last 30 years. By analysing the trend of recently published papers, I can assess which ones are projected to be most influential. Keywords: Fisheries economics, Marine Resource Economics, ISI. JEL Classification Code: Q22.Fisheries economics, Marine Resource Economics, ISI, Resource /Energy Economics and Policy, Q22,
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