In situMeasurement of Self-Heating in Intrinsic Tunneling Spectroscopy

Abstract

Using advanced sample engineering we performed simultaneous measurements of interlayer tunneling characteristics and in situ monitoring of temperature in Bi(2)Sr(2)CaCu(2)O(8 + delta) (Bi-2212) mesas. Together with a systematic study of size dependence of interlayer tunneling, this allowed unambiguous discrimination between artifacts of self-heating and gaps in the electronic spectra of Bi-2212. Such a confident spectroscopic information, which is not affected by self-heating or surface deterioration, was obtained for the first time for a high-T(c) superconductor. We also derived general expressions and formulated main principles of self-heating valid for a large variety of materials.

Terahertz wave emission from intrinsic Josephson junctions in high-Tcsuperconductors

“…All of our radiating samples have a Josephson critical current density of about 100 A cm −2 . All of them show backbending above 1.5 V where heating severely affects the local mesa temperature [30,31]. A voltage of 1.5 V corresponds to 2 mV per junction, which indicates that a fundamental frequency of 1 THz may be possible before heating severely affects the mesa.…”

Analysis of the pseudogap-related structure in the tunnel spectra of superconducting Bi2Sr2CaCu2O8+δ revealed by break-junction technique

“…Namely, (i) we consider the DHSs as remnants of the smeared peaks originated from the CDW (PG) gapping, and (ii) there are no fixed values of the superconducting, D, and dielectric (CDW), S, gaps, because all BSCCO samples, whatever their quality, turn out intrinsically inhomogeneous. The second assumption is a well established experimental fact [6,17,18,23,24], whereas the first one is a plausible hypothesis [14] resting upon the observations of regular domains with stripe order [31] and the analysis of the diss i m i l a r i t i e s b e t w e e n g e n u i n e s u p e r c o n d u c t i n g phenomena and PG manifestations [11,[13][14][15]32,33].…”

Thermal Management in Large Bi2212 Mesas Used for Terahertz Sources

“…The very large current density and close proximity of neighboring junctions in the crystal structure of Bi2212 could be expected to cause similar heating effects. Faced with this issue, researchers have found solutions to reduce heating: use of short current pulses [5], [6]; reduction of the current density by increasing the c-axis resistance through intercalation of inert molecules, e.g., , , within the Bi-O bilayer of Bi2212 [7]; and reduction of the mesa volume which has been discussed in detail both experimentally [8], [9] and theoretically [10], [11].…”