3,388 research outputs found
Avoiding Liquidity Traps
Once the zero bound on nominal interest rates is taken into account, Taylor-type interest-rate feedback rules give rise to unintended self-fulfilling decelerating inflation paths and aggregate fluctuations driven by arbitrary revisions in expectations. These undesirable equilibria exhibit the essential features of liquidity traps, as monetary policy is ineffective in bringing about the government's goals regarding the stability of output and prices. This paper proposes several fiscal and monetary policies that preserve the appealing features of Taylor rules, such as local uniqueness of equilibrium near the inflation target, and at the same time rule out the deflationary expectations that can lead an economy into a liquidity trap.TAYLOR RULES; LIQUIDITY TRAPS; ZERO BOUND ON NOMINAL INTEREST RATES.
Monetary Policy and Multiple Equilibria
In this paper, we characterize conditions under which interest rate feedback rules wherby the nominal interest rate is set as an increasing function of the inflation rate generate multiple equilibria. We show that these conditions depend not only on the fiscal regime (as emphasized in the fiscal theory of the price level) but also on the way in which money is assumed to enter preferences and technology. We analyze this issue in flexible and sticky price environments.MONETARY POLICY ; PRICES ; INTEREST RATE
collective mode as A Raman resonance in cuprate superconductors
We discuss the possible existence a spin singlet excitation with charge
(-mode) originating the Raman resonance in cuprate
superconductors. This -mode relates the -wave superconducting singlet
pairing channel to a -wave charge channel. We show that the boson
forms a particle-particle bound state below the threshold of the
particle-hole continuum where is the maximum -wave gap. Within a
generalized random phase approximation and Bethe-Salpether approximation study,
we find that this mode has energies similar to the resonance observed by
Inelastic Neutron Scattering (INS) below the superconducting (SC) coherent peak
at in various SC cuprates compounds. We show that it is a very good
candidate for the resonance observed in Raman scattering below the
peak in the symmetry. Since the -mode sits in the channel,
it may be observable via Raman, X -ray or Electron Energy Loss Spectroscopy
probes
Three energy scales in the superconducting state of hole-doped cuprates detected by electronic Raman scattering
We explored by electronic Raman scattering the superconducting state of
Bi-2212 single crystal by performing a fine tuned doping study. We found three
distinct energy scales in A1g, B1g and B2g symmetries which show three distinct
doping dependencies. Above p=0.22 the three energies merge, below p=0.12, the
A1g scale is no more detectable while the B1g and B2g scales become constant in
energy. In between, the A1g and B1g scales increase monotonically with
under-doping while the B2g one exhibits a maximum at p=0.16. The three
superconducting energy scales appear to be an universal feature of hole-doped
cuprates. We propose that the non trivial doping dependence of the three scales
originates from Fermi surface topology changes and reveals competing orders
inside the superconducting dome.Comment: 6 pages, 5 figure
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