Drastic improvement of surface structure and current-carrying ability in YBa2Cu3O7 films by introducing multilayered structure

Pan, Alexey V.; Pysarenko, Serhiy; Dou, Shi Xue

doi:10.1063/1.2211051

Cited by 74 publications

(66 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…4,34,68,74 , films deposited at low repetition rates had smoother surfaces, which is in opposite to our results provided in Table I. However in those works, the roughness was studied on thicker films (> 200 nm) with highly developed surface structures containing outgrowths, holes, pinholes and other defects formed due to incomplete island coalescence of relatively thick films 4,34 or stress-guided surface roughening after complete coalescence 5,33,35 . Upon deposition on highly developed surface with low deposition rates adatoms have more time to diffuse to sites with high coordination number, reducing roughness as observed in Refs.…”

Section: B Ybco Thin Filmscontrasting

confidence: 56%

“…The YBCO PLD films of the optimal thickness with the highest J c (B a ) are usually associated with rather advanced island structure 61-63 with pronounced topology and rather high surface roughness 6,33 (unless special techniques are employed to reduce it 33,35 ). The developed structure and its corresponding topography hinder the study of the island growth and structure.…”

Section: B Ybco Thin Filmsmentioning

confidence: 99%

“…On the other hand, the top layers of the film with a significant thickness may have the least effect on the properties 66 . Thus, it is natural to associate the growth of 25 nm thick films with their superconducting properties, keeping in mind that the surface may still be one of the factors affecting the behaviour of the films 33,35 . These structures indicate Stranski-Krastanov growth mode, as expected for YBCO films on STO substrates by PLD 13,15,62-64,67-69 .…”

Section: B Ybco Thin Filmsmentioning

confidence: 99%

“…Quasi-single-crystal c-oriented YBCO thin films were produced on 5 × 5 mm size SrTiO 3 (STO) substrates using standard pulsed-laser deposition (PLD) 33,35 . Deposition was performed by KrF excimer laser with the wave-length of 248 nm.…”

Section: A Pld Of Ybco and Fept Thin Filmsmentioning

confidence: 99%

“…In thicker films, the surface becomes rough and their properties degrade, unless a multilayered structure is introduced 35 . In thinner films, the integral capabilities of the films are reduced.…”

Section: Introductionmentioning

confidence: 99%

See 4 more Smart Citations

Significant tunability of thin film functionalities enabled by manipulating magnetic and structural nano-domains

Golovchanskiy

Pan

Fedoseev

et al. 2014

Applied Surface Science

Self Cite

View full text Add to dashboard Cite

The influence of laser frequency on the structure and physical properties of thin films grown by pulsed laser deposition has been studied. Different types of thin films, hard ferromagnetic FePt L10 and quasi-single crystal superconducting YBa2Cu3O7 (YBCO), have been used for demonstration of the effect. Significant structural modifications have been obtained for the films with similar thicknesses. These modifications are shown to dramatically control their corresponding properties, providing an instrumental ability for tuning the practical characteristics of the films by changing the laser frequency of their deposition. In particular, 20-fold increase of coercive field and modification of demagnetization mechanism are obtained for FePt films by varying the frequency from 1 Hz to 6 Hz. Over a similar frequency range, a strong dependence on the laser frequency is discovered for the YBCO films for the critical current density behavior as a function of the applied magnetic field [ Jc(Ba)] with the unexpected reversal of Jc(Ba) curves with temperature. The mechanisms of structure modifications and corresponding property variations are proposed. The influence of laser frequency on the structure and physical properties of thin films grown by pulsed laser deposition has been studied. Different types of thin films, hard ferromagnetic FePt L10 and quasi-single crystal superconducting YBa2Cu3O7 (YBCO), have been used for demonstration of the effect. Significant structural modifications have been obtained for the films with similar thicknesses. These modifications are shown to dramatically control their corresponding properties, providing an instrumental ability for tuning the practical characteristics of the films by changing the laser frequency of their deposition. In particular, 20-fold increase of coercive field and modification of demagnetization mechanism are obtained for FePt films by varying the frequency from 1 Hz to 6 Hz. Over a similar frequency range, a strong dependence on the laser frequency is discovered for the YBCO films for the critical current density behaviour as a function of the applied magnetic field [Jc(Ba)] with the unexpected reversal of Jc(Ba) curves with temperature. The mechanisms of structure modifications and corresponding property variations are proposed.

show abstract

Section: B Ybco Thin Filmscontrasting

confidence: 56%

Section: B Ybco Thin Filmsmentioning

confidence: 99%

Section: B Ybco Thin Filmsmentioning

confidence: 99%

Section: A Pld Of Ybco and Fept Thin Filmsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Significant tunability of thin film functionalities enabled by manipulating magnetic and structural nano-domains

Golovchanskiy

Pan

Fedoseev

et al. 2014

Applied Surface Science

Self Cite

View full text Add to dashboard Cite

show abstract

Enhancing Properties of High‐Temperature Superconducting Step‐Edge Josephson Junctions by Nano‐Multilayers with a Small Mismatch

Pan

Shcherbakova

Fedoseev

et al. 2014

Adv Materials Inter

View full text Add to dashboard Cite

activated motion in these superconducting structures. [ 6 ] One of the approaches to minimize the 1/f noise caused by vortex motion is improvement of pinning properties and, hence, the critical current density ( J c ) of the superconducting fi lm. Recently, the noise performance of HTS SQUID has been improved in a magnetic environment by using YBCO fi lm with a large thickness and high J c value. [ 8 ] We have also demonstrated that fi lms with better structural integrity (smooth, no holes) minimize fl ux creep and vortex hopping in alternating magnetic fi elds and have lower 1/f noise. [ 9 ] Thus, the materials technology needs for qubits are similar to the requirements of SQUID applications, also having Josephson junctions as their basic element. High quality YBCO Josephson junctions play a key-role in the successful implementation of HTS superconducting circuits at 77 K. [ 6 ] This is mainly due to YBCO material properties, resulting from the complexity of structural characteristics and having strong infl uence on the transport properties of YBCO. [ 10 ] A range of different types of YBCO junctions have been engineered. [ 10 ] Among them, stepedge junctions are singled out due to their low cost, relatively high characteristic voltage (the so-called I R c n value of 100 to 400 μV at 77 K, [ 7,11 ] where I c is the critical current and R n is the resistance in the normal state), and excellent integrability and the scalability of the junctions. These features enable miniaturization and high effi ciency of electronic circuits, as well as applications in magnetic sensing and terahertz (THz) imaging. [ 12,13 ] Therefore, the combined enhancement of fl ux pinning, critical current and microstructure in the YBCO junctions is a crucial task for obtaining tailored junction properties towards the well-defi ned requirements. [ 1 ] In this work, we demonstrate a new straightforward, but effective multilayering approach for fabrication of HTS step-edge junctions with signifi cantly enhanced characteristics. The alternation of main YBCO and intermediate NdBa 2 Cu 3 O 7 (NdBCO) superconducting layers was shown to dramatically improve surface morphology of 1 μm thick fi lms. [ 14 ] Furthermore, this architecture resulted in considerable enhancement of fl ux pinning and current-carrying ability over a wide range of magnetic fi elds and temperatures. We have successfully managed to apply this technology to YBCO step-edge junctions and to demonstrate signifi cant enhancement of transport and structural properties in these junctions. This approach is preferred over the fabrication of thick fi lm, [ 8 ] because it enables structural tailoring with simultaneous adjustment of transport properties required for junction performance. Thus, the multilayered deposition is offering a new promising approach for applications in HTS-based electronics.Recent signifi cant progress in superconducting qubits (based on Josephson junctions) has achieved coherence times approaching to the practically required for quantum computers. [ 1 ] At the same...

show abstract

Tunable pinning effects produced by non‐uniform antidot arrays in YBCO thin films

et al. 2017

View full text Add to dashboard Cite

Uniform, graded and spaced arrays of 3 μm triangular antidots in pulsed laser deposited YBa 2 Cu 3 O 7 (YBCO) superconducting thin films are compared by examining the improvements in the critical current density J c they produced. The comparison is made to establish the role of their lithographically defined (non-)uniformity and the effectiveness to control and/or enhance the critical current density. It is found that almost all types of non-uniform arrays, including graded ones enhance J c over the broad applied magnetic field and temperature range due to the modified critical state. Whereas uniform arrays of antidots either reduce or produce no effect on J c compared to the original (asdeposited) thin films.

show abstract

Drastic improvement of surface structure and current-carrying ability in YBa2Cu3O7 films by introducing multilayered structure

Cited by 74 publications

References 12 publications

Significant tunability of thin film functionalities enabled by manipulating magnetic and structural nano-domains

Significant tunability of thin film functionalities enabled by manipulating magnetic and structural nano-domains

Enhancing Properties of High‐Temperature Superconducting Step‐Edge Josephson Junctions by Nano‐Multilayers with a Small Mismatch

Tunable pinning effects produced by non‐uniform antidot arrays in YBCO thin films

Contact Info

Product

Resources

About