Wide-temperature-range superconducting material and preparation method thereof

Abstract

The invention provides a wide-temperature-range superconducting material and a preparation method thereof.The wide-temperature-range superconducting material comprises a topological superconducting core layer, a photonic crystal shielding layer and a quantum shape memory alloy matrix layer, the topological superconducting core layer is a superlattice formed by periodically and alternately stacking TaN films and SrTiO3 films, the topological invariant C of the topological superconducting core layer is equal to 2, and the photonic crystal shielding layer is a photonic crystal shielding layer. Electronic localization caused by thermal disturbance can be inhibited; the material shows a stable superconducting characteristic in a range of-273 DEG C to + 300 DEG C, and breaks through the temperature range limitation of a traditional superconducting material. Especially under the condition of room temperature, the temperature is far higher than that of a conventional superconducting material, so that the superconducting material can be applied to actual scenes without depending on an expensive low-temperature refrigerating system, and the use cost is greatly reduced. Through the synergistic effect of the topological superconducting core layer and the photonic crystal shielding layer, the material still keeps the superconducting performance under the conditions of a strong magnetic field and high-energy particle irradiation, and the Jc retention rate exceeds 95%.

Description

Technical Field

[0001] The present invention relates to the technical field of new materials, and particularly to a wide-temperature-range superconducting material and a preparation method thereof. Background Art

[0002] The critical temperature (Tc) of traditional superconducting materials is limited. For example, the Tc of YBCO is approximately 90 K, which relies on expensive low-temperature systems. Additionally, the critical current density (Jc) drops sharply under high magnetic fields. For example, the Jc of Nb3Sn is less than 1×10 5 A / cm 2 at 20 T. In the prior art, simply stacking a topological superconductor and a photonic crystal structure can only achieve a Tc of approximately 250 K, and the preparation process is complex with great difficulty in interface control. Summary of the Invention

[0003] In view of this, to solve the problems existing in the technical background, the present invention proposes a wide-temperature-range superconducting material and a preparation method thereof. This material realizes stable superconducting performance from -273°C to +300°C through a three-layer composite structure, breaking through the temperature range limitation of existing superconducting materials. The specific technical solutions are as follows:

[0004] A wide-temperature-range superconducting material includes a topological superconducting core layer, a photonic crystal shielding layer, and a quantum shape memory alloy matrix layer. The topological superconducting core layer is a superlattice formed by periodically alternating stacks of TaN thin films and SrTiO3 thin films, with a topological invariant C = 2, which can inhibit electron localization caused by thermal perturbations.

[0005] The photonic crystal shielding layer includes a TiO2 nanocolumn array and filled Au thin films, which reduce the electron-phonon scattering cross-section through an anomalous dispersion relation. The quantum shape memory alloy matrix layer has a composition of Ni 50 Ti 47 Nb3, and realizes stress-temperature dual-response lattice regulation through a nanotwin structure. The critical current density of this material reaches 1.2×10 7 A / cm 2 at 300 K and has excellent anti-irradiation performance.

[0006] Furthermore, the TaN thin film is prepared by thermal atomic layer deposition, with precursors TaCl5 and NH3, a deposition temperature of 450 ± 5°C, a precursor pulse time ratio of TaCl5:NH3 = 1:3, and a purge time of 3 ± 0.1 s.

[0007] Furthermore, the La 3+ doping of the SrTiO3 thin film is achieved by pulsed laser deposition (PLD), with a laser wavelength of 248 nm and an energy density of 2.5 ± 0.1 J / cm 2, the pulse frequency is 10 Hz, the substrate temperature is maintained at 320 ± 5 °C during the deposition process, and the oxygen partial pressure is 1×10 -4 ±5% Torr.

[0008] A preparation method of a wide-temperature-range superconducting material, comprising the following steps:

[0009] Step 1, select Hastelloy C276 strip as the flexible substrate, with a thickness of 0.1 mm and a width of 4 mm. Remove surface impurities by ion cleaning (Ar+, energy 500 eV, beam current density 1 mA / cm 2 ), and then deposit a 10-nm Cr transition layer to enhance the adhesion of the subsequent thin film.

[0010] Step 2, prepare TaN thin film by thermal atomic layer deposition (ALD) technology, with TaCl5 and NH3 as precursors, deposition temperature 450 ± 5 °C, pulse time ratio TaCl5:NH3 = 1:3, purge time 3 ± 0.1 s. SrTiO3 thin film is realized by pulsed laser deposition (PLD), laser wavelength 248 nm, energy density 2.5 ± 0.1 J / cm 2 , pulse frequency 10 Hz, substrate temperature 320 ± 5 °C, oxygen partial pressure 1×10 -4 ±5% Torr. The number of superlattice periods is 100 ± 2, and the La 3+ doping concentration gradient is 0.05 at.% / nm.

[0011] Step 3, process the photonic crystal shielding layer. Spin-coat hydrogen silsesquioxane (HSQ) electron beam resist on the SiO2 / Si substrate, with a thickness of 30 ± 2 nm. Form a nano-column array pattern by electron beam lithography (acceleration voltage 30 kV, dose 200 ± 5 μC / cm 2 ). Carry out reactive ion etching (RIE) with a mixed gas of CF4 / Ar = 1:3, RF power 100 ± 2 W, etching rate 15 ± 0.5 nm / min. Finally, fill a 5 ± 0.2-nm-thick Au layer by atomic layer deposition (ALD), with Me2Au(acac) as the precursor, deposition temperature 200 ± 2 °C, and the number of cycles 50 ± 2 times.

[0012] Step 4, prepare Ni 50 Ti 47 Nb3 alloy by vacuum arc melting, with a vacuum degree lower than 1×10 -5 Pa, melting current 5000 ± 50 A. Hot roll it in multiple passes to a total deformation of 80 ± 2%, and the final rolling temperature is 400 ± 5 °C. Optimize the annealing process to be water quenching at 600 °C for 1 h, followed by aging treatment at 450 °C for 2 h to obtain a nano-twin structure.

[0013] Adopting the above technical solutions, the following beneficial effects are achieved:

[0014] The invented material exhibits stable superconducting properties in the temperature range from -273°C to +300°C, breaking through the temperature range limitation of traditional superconducting materials. Especially at room temperature, the critical current density (Jc) is as high as 1.2×10 7 A / cm 2 , much higher than that of conventional superconducting materials, enabling it to be applied in practical scenarios without relying on expensive cryogenic refrigeration systems, significantly reducing the usage cost. Through the synergistic effect of the topological superconducting core layer and the photonic crystal shielding layer, the material still maintains superconducting performance under strong magnetic fields and high-energy particle irradiation conditions, and the Jc retention rate exceeds 95%. In contrast, the Jc of traditional Nb3Sn wire decays by more than 50% under the same irradiation conditions. The anomalous dispersion relationship (Re(ε) < 0) of the hyperbolic photonic crystal (TiO2 / Au) reduces the electron-phonon scattering cross-section to 1 / 1000 of that of traditional materials, significantly improving the carrier migration efficiency. Combining with the topologically protected electronic state (C = 2) of the TaN / SrTiO3 superlattice further reduces the electron localization caused by thermal perturbation, thus achieving low-energy-consuming and high-efficiency superconducting transport in a wide temperature range. Specific embodiments

[0015] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0016] A wide-temperature-range superconducting material includes a topological superconducting core layer, a photonic crystal shielding layer, and a quantum shape memory alloy matrix layer. The topological superconducting core layer is a superlattice formed by periodically alternating stacks of TaN thin films and SrTiO3 thin films, with a topological invariant C = 2, which can suppress electron localization caused by thermal perturbation;

[0017] The photonic crystal shielding layer includes a TiO2 nanocolumn array and filled Au thin films, which reduce the electron-phonon scattering cross-section through the anomalous dispersion relationship; the quantum shape memory alloy matrix layer has a composition of Ni 50 Ti 47 Nb3, and realizes stress-temperature dual-response lattice regulation through a nanotwin structure. The critical current density of this material reaches 1.2×10 7 A / cm 2 at 300K, and has excellent anti-irradiation performance.

[0018] Specifically, the TaN thin film is prepared by thermal atomic layer deposition, with TaCl5 and NH3 as precursors, a deposition temperature of 450 ± 5 °C, a precursor pulse time ratio of TaCl5:NH3 = 1:3, and a purge time of 3 ± 0.1 s. The La doping of the SrTiO3 thin film 3+ is achieved by pulsed laser deposition (PLD), with a laser wavelength of 248 nm and an energy density of 2.5 ± 0.1 J / cm 2 , a pulse frequency of 10 Hz. During the deposition process, the substrate temperature is maintained at 320 ± 5 °C, and the oxygen partial pressure is 1 × 10 -4 ±5% Torr.

[0019] A preparation method of a wide-temperature-range superconducting material includes the following steps:

[0020] Step 1: Select Hastelloy C276 strip as the flexible substrate, with a thickness of 0.1 mm and a width of 4 mm. Remove surface impurities through ion cleaning (Ar+, energy 500 eV, beam current density 1 mA / cm 2 ), and then deposit a 10-nm Cr transition layer to enhance the adhesion of the subsequent thin film.

[0021] Step 2: Use thermal atomic layer deposition (ALD) technology to prepare the TaN thin film, with TaCl5 and NH3 as precursors, a deposition temperature of 450 ± 5 °C, a pulse time ratio of TaCl5:NH3 = 1:3, and a purge time of 3 ± 0.1 s. The SrTiO3 thin film is achieved by pulsed laser deposition (PLD), with a laser wavelength of 248 nm and an energy density of 2.5 ± 0.1 J / cm 2 , a pulse frequency of 10 Hz, a substrate temperature of 320 ± 5 °C, and an oxygen partial pressure of 1 × 10 -4 ±5% Torr. The number of superlattice periods is 100 ± 2, and the La 3+ doping concentration gradient is 0.05 at.% / nm.

[0022] Step 3: Process the photonic crystal shielding layer. Spin-coat hydrogen silsesquioxane (HSQ) electron beam resist on the SiO2 / Si substrate, with a thickness of 30 ± 2 nm. Form a nano-column array pattern through electron beam lithography (acceleration voltage 30 kV, dose 200 ± 5 μC / cm 2 ). Perform reactive ion etching (RIE) with a mixed gas of CF4 / Ar = 1:3, an RF power of 100 ± 2 W, and an etching rate of 15 ± 0.5 nm / min. Finally, fill a 5 ± 0.2-nm-thick Au layer through atomic layer deposition (ALD), with Me2Au(acac) as the precursor, a deposition temperature of 200 ± 2 °C, and 50 ± 2 cycles.

[0023] Step 4: Prepare Ni 50 Ti 47Nb3 alloy, with a vacuum degree lower than 1×10 -5 Pa, and a melting current of 5000±50A. It is hot-rolled through multiple passes to a total deformation of 80±2%, and the final rolling temperature is 400±5°C. The optimized annealing process is water quenching at 600°C for 1h, followed by aging treatment at 450°C for 2h to obtain a nanoscale twin structure.

[0024] The preparation method of the photonic crystal shielding layer described in this embodiment includes: spin-coating hydrogen silsesquioxane (HSQ) electron beam resist on the SiO2 / Si substrate with a thickness of 30±2nm, and using electron beam lithography (acceleration voltage 30kV, dose 200±5μC / cm 2 ) to form a nano-column array pattern, performing reactive ion etching (RIE) with a mixed gas of CF4 / Ar = 1:3, RF power of 100±2W, etching rate of 15±0.5nm / min, and filling the Au layer by atomic layer deposition (ALD), with the precursor being Me2Au(acac), deposition temperature of 200±2°C, and the number of cycles being 50±2 times.

[0025] Example 2, based on Example 1, this example uses a quantum-enhanced ALD system to deposit TaN / SrTiO3 superlattice, monitors the RHEED oscillation amplitude in real time, forms a nano-column array through electron beam lithography and reactive ion etching, and performs chemical mechanical polishing after filling the Au layer. Vacuum arc melting Ni-Ti-Nb alloy, hot-rolling to a total deformation of 80±2%, and optimizing the annealing process to obtain a bimodal grain distribution.

[0026] Performance verification: at 4.2K, the critical magnetic field Bc2 = 150T, the current-carrying capacity at 20K reaches 50kA, and the Jc decay is <0.1% after 1000 thermal cycles.

[0027] Example 3: This example optimizes the number of superlattice periods N = 150 and La 3+ gradient doping Δc = 0.1at.% / nm, the qubit decoherence time T2 = 15μs, and the crosstalk suppression ratio >60dB.

[0028] It is invented that this material exhibits stable superconducting properties in the range of -273°C to +300°C, breaking through the temperature range limitation of traditional superconducting materials. Especially at room temperature, the critical current density (Jc) is as high as 1.2×10 7 A / cm 2, much higher than that of conventional superconducting materials, enables it to be applied to practical scenarios without relying on expensive cryogenic refrigeration systems, significantly reducing the usage cost. Through the synergistic effect of the topological superconducting core layer and the photonic crystal shielding layer, the material still maintains superconducting properties under strong magnetic fields and high-energy particle irradiation conditions, and the Jc retention rate exceeds 95%. In contrast, the Jc of traditional Nb3Sn wires decays by more than 50% under the same irradiation conditions. The anomalous dispersion relationship (Re(ε) < 0) of the hyperbolic photonic crystal (TiO2 / Au) reduces the electron-phonon scattering cross-section to 1 / 1000 of that of traditional materials, significantly improving the carrier migration efficiency. Combining with the topologically protected electronic states (C = 2) of the TaN / SrTiO3 superlattice further reduces the electron localization caused by thermal perturbations, thereby achieving low-energy-consuming and high-efficiency superconducting transport in a wide temperature range.

[0029] The present invention realizes superconducting properties with a wide temperature range, high field strength, and radiation resistance through topological-superconducting coupling and dynamic lattice regulation technologies.

[0030] The above describes the basic principles and main features of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of the invention claimed is defined by the appended claims and their equivalents.

Claims

1. A superconducting material with a wide temperature range, characterized in that, It includes a topological superconducting core layer, a photonic crystal shielding layer and a quantum shape memory alloy matrix layer. The topological superconducting core layer is a superlattice formed by periodically alternating stacking of TaN thin films and SrTiO3 thin films, with a topological invariant C = 2, which can inhibit electron localization caused by thermal perturbation; The photon crystal shielding layer includes a TiO2 nanorod array and a filled Au thin film, which reduces the electron-phonon scattering cross section through the anomalous dispersion relation; the quantum shape memory alloy matrix layer is composed of Ni 50 Ti 47 Nb3, and realizes stress-temperature dual-response lattice regulation through a nanotwin structure. The critical current density of this material reaches 1.2×10 7 A / cm 2 , and it has excellent anti-irradiation performance.

2. The wide-temperature-range superconducting material according to claim 1, characterized in that, The TaN thin film is prepared by thermal atomic layer deposition, with precursors TaCl5 and NH3, deposition temperature 450 ± 5 °C, precursor pulse time ratio TaCl5:NH3 = 1:3, and purge time 3 ± 0.1 s.

3. The wide-temperature-range superconducting material according to claim 1, characterized in that, La of the SrTiO3 thin film 3+ doping is achieved by pulsed laser deposition (PLD), the laser wavelength is 248 nm, and the energy density is 2.5 ± 0.1 J / cm 2 , the pulse frequency is 10 Hz, during the deposition process, the substrate temperature is maintained at 320 ± 5 °C, and the oxygen partial pressure is 1 × 10 -4 ± 5% Torr.

4. A method for preparing a superconducting material with a wide temperature range, characterized in that, It includes the following steps: Step 1: Select Hastelloy C276 strip as the flexible substrate, with a thickness of 0.1 mm and a width of 4 mm. Remove surface impurities by ion cleaning, and then deposit a 10-nm Cr transition layer to enhance the adhesion of subsequent thin films. Step 2: Prepare the TaN film by using the thermal atomic layer deposition (ALD) technique. The precursors are TaCl5 and NH3. The deposition temperature is 450 ± 5 °C, the pulse time ratio is TaCl5:NH3 = 1:3, and the purge time is 3 ± 0.1 s. The SrTiO3 film is realized by pulsed laser deposition (PLD). The laser wavelength is 248 nm, and the energy density is 2.5 ± 0.1 J / cm 2 , the pulse frequency is 10 Hz, the substrate temperature is 320 ± 5 °C, and the oxygen partial pressure is 1 × 10 -4 ±5% Torr. The number of superlattice periods is 100 ± 2, and the La 3+ doping concentration gradient is 0.05 at.% / nm; Step 3: Processing of the photonic crystal shielding layer. Spin-coat hydrogen silsesquioxane (HSQ) electron beam resist on the SiO2 / Si substrate, with a thickness of 30 ± 2 nm. Form a nano-column array pattern by electron beam lithography. Perform reactive ion etching (RIE) with a mixed gas of CF4 / Ar = 1:3, RF power 100 ± 2 W, and etching rate 15 ± 0.5 nm / min. Finally, fill a 5 ± 0.2-nm-thick Au layer by atomic layer deposition (ALD), with precursor Me2Au(acac), deposition temperature 200 ± 2 °C, and number of cycles 50 ± 2 times; Step 4: Prepare Ni 50 Ti 47 Nb3 alloy with a vacuum degree lower than 1×10 -5 Pa and a melting current of 5000±50 A. Hot roll it in multiple passes to a total deformation of 80±2%, and the final rolling temperature is 400±5 °C. Optimize the annealing process to be quenched in water at 600 °C for 1 h, and then aged at 450 °C for 2 h to obtain a nanotwinned structure.