Research Topics:
Research Topics:
(A) Nanoelectronics group
Spintronics
SL-MTJ
(superlattice based MTJ) and MTJ (magnetic tunnel junctions)
SS-MRAM
(superlattice-based STT-MRAM or SL-STT-MRAM), STT- MRAM (spin-transfer torque
MRAM), and MRAM (magnetoresistive random access memory)
Read More
Graphene
and topological insulator, and spin-valve
(B) Photonics group
Photonic
crystals, topological photonics, and quasicrystals
Waveguides,
integrated optics, and multilayers
Microring
resonators
Graphene
SS-MRAM:
A superlattice-based STT-MRAM with ultra-high performance
Magnetic random-access memory (MRAM) is a type of non-volatile memory that operates using spintronics. It offers several advantages, including low energy consumption, zero standby power, non-volatility, high endurance, and high density. The magnetic tunnel junction (MTJ) is the fundamental memory unit in MRAM and the core component of the device.
A research team at the Electronic and Photonics Laboratory, National Taiwan University, has developed a spin-transfer torque-based magnetic random-access memory (STT-MRAM) featuring a superlattice barrier, referred to as SS-MRAM or SL-STT-MRAM. This innovative SS-MRAM achieves ultra-low power consumption, an ultra-high magnetoresistance ratio (MR ratio), high-speed switching, and a low resistance-area product (RA). Unlike traditional STT-MRAM, which uses single-crystalline (001) MgO, SS-MRAM employs an artificial material known as a superlattice as the barrier layer. This superlattice is composed of alternating metal and insulating layers, where amorphous materials can replace single-crystalline insulators. Consequently, SS-MRAM significantly enhances performance, improves reliability, and simplifies the fabrication process compared to traditional STT-MRAM.
Theoretical predictions indicate that SS-MRAM can substantially reduce the write power and RA value of conventional STT-MRAM, while dramatically improving the MR ratio and switching speed. These results have already been published in various international journals and conferences.
Notably, the insulating layer in SS-MRAM can be made from any amorphous material, eliminating the need for highly demanding fabrication processes required for single-crystalline materials. This makes the manufacturing process of SS-MRAM simpler and more accessible. Furthermore, since SS-MRAM uses stable amorphous materials rather than less stable single-crystalline materials, it avoids degradation caused by repeated write operations that could impact performance. As a result, the reliability and durability of SS-MRAM are significantly enhanced, approaching the levels of conventional DRAM or SRAM.
Recently, we have completed experimental validation of SL-MTJ. Compared to conventional MgO-MTJ, the RA can be significantly reduced while the MR is improved. Furthermore, TEM imaging reveals that the superlattice barrier layer exhibits a non-crystalline arrangement, resulting in improved device endurance, simplified manufacturing, higher yield, and reduced sensitivity to temperature variations. These characteristics make it particularly suitable for embedded memory applications. Moving forward, we will continue testing SL-MTJ samples and proceed with the fabrication of SS-MRAMs. Subsequent steps will include endurance evaluations. We are currently seeking industry collaborations to further develop, test, and scale the performance of SS-MRAMs.
Related publications
A. News and Website Reports
[1] R. Mertens, 2019, “New super-lattice SL-STT-MRAM enable faster and more efficient memory architecture,” MRAM-Info, Posted: Dec 23, 2019. Read More
[2] Nanowerk News, 2020, “A superlattice based STT-MRAM with extra-high performance,” Nanowerk, Posted: Jan 17, 2020. Read More
[3] DigiTimes, 2020, “Taiwan university develops next-gen memory technology,” DigiTimes, Posted: Jun. 10, 2020. Read More
[4] 台大校訊1422期:“臺大工科系薛文証教授團隊開發次世代記憶體SS-MRAM獲MRAM-Info以及Nanowerk News報導”(2020/2/5) 報導連結；
台灣大學焦點新聞:“臺大工科系薛文証教授團隊開發次世代記憶體SS-MRAM獲報導”(2020/02/10) 報導連結；
臺灣大學第174期校友電子報:“臺大工科系薛文証教授團隊開發次世代記憶體SS-MRAM獲MRAM-Info以及Nanowerk News報導”(2020/3) 報導連結
[5] 台灣大學工學院簡訊230期:“【工科海洋系薛文証教授團隊】開發次世代記憶體SS-MRAM獲MRAM-Info專業網站撰文介紹”(2020/2/15) 報導連結
[6] DigiTimes科技網: “台大團隊突破SS-MRAM關鍵技術 搶攻次世代夢幻記憶體”(2020/6/10) 報導連結
B. Scientific Journals and Conferences
[1] C. H. Chen and W. J. Hsueh*, 2014, “Enhancement of tunnel magnetoresistance in magnetic tunnel junction by a superlattice barrier,” Appl. Phys. Lett., Vol. 104, pp. 042405. Read More
[2] C. H. Chen, C. H. Chang, Y. H. Cheng, and W. J. Hsueh*, 2015, “Ultrahigh tunnel magnetoresistance using an artificial superlattice barrier with copper and aluminum oxide,” Europhys. Lett. Vol. 111, pp. 47005. Read More
[3] C. H. Chen, Y. H. Cheng, C. W. Ko, and W. J. Hsueh*, 2015, “Enhanced spin-torque in double-barrier magnetic tunnel junctions by a nonmagnetic-metal spacer,” Appl. Phys. Lett., Vol. 107, pp. 152401. Read More
[4] C. H. Chen, P. Tseng, C. W. Ko, and W. J. Hsueh*, 2017, “Huge spin transfer torque in a magnetic tunnel junction by a superlattice barrier,” Phys. Lett. A, Vol. 381, pp. 3124-3128. Read More
[5] P. Tseng and W. J. Hsueh*, 2018, “Enhancement of spin-transfer torque in superlattice-barrier magnetic tunnel junctions,” Global Conference on Magnetic and Magnetism Materials (GMMM 2018), July, 23-24, Osaka, Japan. Read More
[6] P. Tseng and W. J. Hsueh*, 2019, “Ultra-giant magnetoresistance in graphene-based spin valves with gate-controlled potential barriers,” New J. Phys., Vol. 21, No. 113035. Read More
[7] P. Tseng, Z. Y. Chen and W. J. Hsueh*, 2020, “Superlattice-barrier magnetic tunnel junctions with half-metallic magnets,” New J. Phys., Vol. 22, No. 093005. Read More
[8] P. Tseng, J. W. Chen and W. J. Hsueh*, 2021 “Huge magnetoresistance in topological insulator spin-valves at room temperature,” Sci Rep, Vol. 11, No. 11717. Read More
[9] C. P. Wang, S. H. Cheng and W. J. Hsueh*, 2023 “High spin current density in gate-tunable spin-valves based on graphene nanoribbons,” Sci Rep, Vol. 13, No.9234. Read More
[10] J. C. Su, S. H. Cheng, S. Y. Huang and W. J. Hsueh*, 2024, “Magnetic tunnel junctions with superlattice barriers,” J. Appl. Phys., Vol. 136, No. 103902. Read More
Journal
papers
(2010-2024):
1. Shih-Hung Cheng , Ting-I Kuo , Er-Feng Hsieh, and Wen-Jeng Hsueh*, 2024 “Room-temperature negative differential resistance in gate-tunable Weyl semimetal transistors,” Results in Physics, Vol. 67, No. 108039. (MOST 112-2221-E-002-018) (SCI, Physics, Multidisciplinary, RF: 23/112=20.53%, IF:4.1 )
2. Shih-Hung Cheng , Ting-I Kuo , Er-Feng Hsieh, and Wen-Jeng Hsueh*, 2024 “Gate-controllable two-dimensional transition metal dichalcogenides for spintronic memory,” Journal of Alloys and Compounds, Vol. 1010, No. 177487. (MOST 112-2221-E-002-018) (SCI, Metallurgy & Metallurgical Engineering, RF: 9/91=9.89%, IF:5.3)
3. Jing-Ci Su, Shih-Hung Cheng, Sin-You Huang, and Wen-Jeng Hsueh*, 2024 “Magnetic Tunnel Junctions with Superlattice Barriers,” J. Appl. Phys., Vol. 136, No. 103902. (MOST 112-2221-E-002-018) (SCI, Physics, Applied, RF: 82/180=45.55%, IF:2.6 )
4. Shih-Hung Cheng, Hsin-He Lin, Yi-Chia Chien, Yu-Chuan Lin, and Wen-Jeng Hsueh*, 2024 “Broadband Terahertz Modulation in Symmetric Gate-controlled Graphene Photonic Crystals,” Carbon, Vol. 229, No. 119535. (MOST 112-2221-E-002-018) (SCI, Materials science, Multidisciplinary, RF: 63/439=14.35%, IF:9.2 )
5. Wen-Chun Huang, Ying Li, Nian-Ho Chang, Wei-Jie Hong, Sin-Ying Wu, Su-Yu Liao, Wen-Jeng Hsueh, Chih-Min Wang, Chun-Ying Huang*, 2024 “Highly stable and selective H2 gas sensors based on light-activated a-IGZO thin films with ZIF-8 selective membranes,” Sensors and Actuators B: Chemical, Vol. 417, pp. 136175. (MOST 111-2221-E-260-010) (SCI, Instruments & Instrumentation, RF: 4/76=5.26%, IF:7.0)
6. Yu-Chuan Lin*, Yi-Chia Chien, Wen-Jeng Hsueh*, 2024 “Topological slow-light in one-dimensional conjugated photonic systems,” Optics Communications, Vol. 558, No. 130369. (MOST-110-222-E-002-176) (SCI, Optics, RF: 61/120=50.8%, IF:2.0 )
7. W. C. Huang, Y. C. Lee, Y. Z. Chen, C. M. Wu, W. J. Hsueh, S. Y. Liao, and C. Y. Huang*, 2023 “Photochemically Activated Mn3O4 Thin Films That Are Produced Using SILAR for Highly Stable Flexible Gas Sensors,” IEEE Sensors Journal, Vol. 23, pp.21001-21009. (MOST 111-2221-E-260-010) (SCI, Instruments & Instrumentation, RF: 14/76=18.4%, IF:4.2)
8. Y. F. Lin, B. C. Dong, S. Y. Liao, B. R. Chen, L. Z. Lin , Y. Y. Chang , M. H. Wu, P. Y. Su, B. C. Chen, W. J. Hsueh, C. Y. Huang *, 2023 “Highly sensitive and stable room-temperature gas sensors based on the photochemically activated p-type CuAlO2 thin films,” Materials Chemistry and Physics, Vol. 309, pp. 128328. (MOST 111-2221-E-260-010) (SCI, Materials science, Multidisciplinary, RF: 160/439=36.4%, IF:4.1)
9. W. C. Huang, Z. C. Tseng, W. J. Hsueh, S. Y. Liao, and C. Y. Huang*, 2023 “X-Ray Detectors Based on Amorphous InGaZnO Thin Films,” IEEE Transactions on Electron Devices, Vol. 70, pp. 3690-3694. (MOST 111-2221-E-260-010) (SCI, Physics, Applied, RF: 74/180=41.1%, IF:2.9)
10. C. P. Wang, S. H. Cheng and W. J. Hsueh*, 2023 “High spin current density in gate-tunable spin-valves based on graphene nanoribbons,” Scientific Reports, Vol. 13, No.9234. (MOST 110-2221-E-002-176 and 111-2221-E-002-194) (SCI, Multidisciplinary sciences, RF: 25/135=18.5%, IF:4.3)
11. P.T. Lin, C. Y. Yu, S. H. Ho, S. W. Pan, J. S. Jhang, Y. X. Zhang, Y. L. Zhang, T. T. Hsieh, H. C. Wang, W. J. Hsueh, and C. Y. Huang*, 2023 “Photochemically-activated p-Type CuGaO2 thin films for highly-stable room-temperature gas sensors,” J. Electrochem. Soc. , Vol. 170, No. 037515. (MOST 111-2221-E-260-010) (SCI, Materials science, coatings & films, RF: 8/23=34.8%, IF: 3.8)
12. Y. C. Lin*, Y. Z. Zhang, S. H. Cheng, C. Y. Huang and W. J. Hsueh*, 2023 “Conjugated topological cavity-states in one-dimensional photonic systems and bio-sensing applications,” iScience, Vol. 26, No. 106400. (MOST-110-2222-E-492-003, MOST-110-222-E-002-176) (SCI, Multidisciplinary sciences, RF: 21/135=15.6%, IF:5.0 )
13. Y. F. Lin, Y. Y. Jiang, B. L. Huang, P. Y. Huang, W. J. Hsueh*, and C. Y. Huang*, 2022 “Low-temperature solution-processed ZnSnO ozone gas sensors using UV-assisted thermal annealing,” J. Electrochem. Soc. , Vol. 169, No. 117505. (MOST 111-2221-E-260-010) (SCI, Materials science, coatings & films, RF: 6/20=30%, IF: 4.365)
14. P. T. Lin, W. C. Huang, J. R. Gong, W. J. Hsueh*, and C. Y. Huang*, 2022 “Radiation hardness of solution-processed amorphous ZnSnO gas sensors against gamma rays,” Microelectron Reliab. , Vol. 139, No. 114803. (MOST 111-2221-E-260-010) (SCI, Electrical engineering, RF: 242/578=41.9%, IF:1.418)
15. Y. C. Lin, B. Y. Chen and W. J. Hsueh*, 2021 “Conjugated topological interface-states in coupled ring resonators,” Scientific Reports, Vol. 11, No.12104. (MOST 106-2221-E-002-119-MY3) (SCI, Multidisciplinary sciences, RF: 13/71=18.3%, IF:4.576 )
16. P. T. Lin, W. C. Huang, Y. Q. Lou, C. Y. Yan, Y. S. Lin, C. L. Chang, P. C. Chang, J. R. Gong, W. J. Hsueh*, and C. Y. Huang*, 2021 “Solution-processed Li-doped ZnSnO metal-semiconductor-metal UV photodetectors,” J. Phys. D, Vol. 54, No. 345107. (MOST 106-2218-E-260-001-MY3) (SCI, Physics, Applied, RF: 31/145=21.4%, IF:2.772)
17. P. Tseng, J. W. Chen and W. J. Hsueh*, 2021 “Huge magnetoresistance in topological insulator spin-valves at room temperature,” Scientific Reports, Vol. 11, No. 11717. (MOST 106-2221-E-002-119-MY3) (SCI, Multidisciplinary sciences, RF: 13/71=18.3%, IF:4.576 )
18. P. T. Lin, J. W. Chang, S. R. Chang, Z. K. Li, W.Z. Chen, J. H. Huang,Y. Z. Ji, W. J. Hsueh*, and C. Y. Huang*, 2021 “A stable and efficient Pt/n-type Ge Schottky contact that uses low-cost carbon paste interlayers,” Crystals, Vol. 11, No. 259. (MOST 106-2218-E-260-001-MY3) (SCI, Crystallography, RF: 10/24=41.7%, IF:2.404)
19. Y. C. Lin, S. H. Tsou and W. J. Hsueh*, 2020 “Tunable light absorption of graphene using topological interface states,” Opt. Lett., Vol. 45, No. 16, pp. 4369-4372. (MOST 106-2221-E-002-119-MY3) (SCI, Optics, RF: 20/97=20.6%, IF:3.443)
20. P. Tseng, Z. Y. Chen and W. J. Hsueh*, 2020, “Superlattice-barrier magnetic tunnel junctions with half-metallic magnets,” New J. Phys., Vol. 22, No. 093005. (MOST 106-2221-E-002-119-MY3 and MOST 105-2221-E-002-136) (SCI, Physics, multidisciplinary, RF: 17/85=20.0%, IF:3.579 )
21. Y. C. Lin, S. H. Chou and W. J. Hsueh*, 2020 “Robust high-Q filter with complete transmission by conjugated topological photonic crystals,” Scientific Reports, Vol. 10, No. 7040. (MOST 106-2221-E-002-119-MY3) (SCI, Multidisciplinary sciences, RF: 13/71=18.3%, IF:4.576 )
22. P. Tseng and W. J. Hsueh*, 2019, “Ultra-giant magnetoresistance in graphene-based spin valves with gate-controlled potential barriers,” New J. Phys., Vol. 21, No. 113035. (MOST 106-2221-E-002-119-MY3 and MOST 105-2221-E-002-136) (SCI, Physics, multidisciplinary, RF: 12/81=14.8%, IF:3.626 )
23. Y. C. Lin, C. H. Tsou and and W. J. Hsueh*, 2018 “Ultra-slow light in one-dimensional Cantor photonic crystals,” Opt. Lett., Vol. 43, No. 17, pp. 4120-4123. (SCI, Optics, RF: 16/95=16.8%, IF:3.866)
24. P. Tseng, C. H. Chen, S. A. Hsu, and W. J. Hsueh*, 2018, “Large negative differential resistance in graphene nanoribbon superlattices,” Phys. Lett. A, Vol. 382, pp. 1427-1431. (SCI, Physics, multidisciplinary, RF: 33/81=40.7%, IF:2.087)
25. C. H. Chen, P. Tseng, C. W. Ko, and W. J. Hsueh*, 2017, “Huge spin transfer torque in a magnetic tunnel junction by a superlattice barrier,” Phys. Lett. A, Vol. 381, pp. 3124-3128. (SCI, Physics, multidisciplinary, RF: 35/78=44.9%, IF:1.863)
26. C. H. Chen, P. Tseng, Y. Y. Yang and W. J. Hsueh*, 2017, “Enhancement of thermal spin transfer torque by double-barrier magnetic tunnel junctions with a nonmagnetic metal spacer,” J. Phys.: Condens. Matter, Vol. 29, pp. 025806. (SCI, Physics, condensed matter, RF: 27/67=40.3%, IF:2.617)
27. C. H. Chen, P. Tseng, and W. J. Hsueh*, 2016, “Quasi-Dirac points in one-dimensional graphene superlattices,” Phys. Lett. A, Vol. 380, pp. 2957-2961. (SCI, Physics, multidisciplinary, RF: 27/79=34.2%, IF:1.772)
28. C. H. Chen, Y. H. Cheng, C. W. Ko, and W. J. Hsueh*, 2015, “Enhanced spin-torque in double-barrier magnetic tunnel junctions by a nonmagnetic-metal spacer,” Appl. Phys. Lett., Vol. 107, pp. 152401. (SCI, Physics, Applied, RF: 28/145=19.3%, IF:3.142)
29. Y. H. Cheng, C. H. Chen, K. Y. Yu, and W. J. Hsueh*, 2015, “Extraordinary light absorptance in graphene superlattices,” Opt. Express, Vol. 23, No. 22, pp. 28755-28760. (SCI, Optics, RF: 14/90=15.6%, IF:3.148)
30. C. H. Chen, C. H. Chang, Y. H. Cheng, and W. J. Hsueh*, 2015, “Ultrahigh tunnel magnetoresistance using an artificial superlattice barrier with copper and aluminum oxide,” Europhys. Lett. Vol. 111, pp. 47005. (SCI, Physics, multidisciplinary, RF: 19/79=24.1%, IF:1.963)
31. C. W. Tsao, Y. H. Cheng and and W. J. Hsueh*, 2015 “High-order microring resonator with perfect transmission using symmetric Fibonacci structures,” Opt. Lett., Vol. 40, No. 18, pp. 4237-4240. (SCI, Optics, RF: 15/90=16.7%, IF:3.040)
32. C. H. Chen, B. S. Chao, and and W. J. Hsueh*, 2015, “Huge magnetoresistance in graphene-based magnetic tunnel junctions with superlattice barriers,” J. Phys. D, Vol. 48, No. 335004, pp. 1-6. (SCI, Physics, Applied, RF: 31/145=21.4%, IF:2.772)
33. C. W. Tsao, Y. H. Cheng and and W. J. Hsueh*, 2015, “Sharp resonance with complete transmission in Thue-Morse microring resonators,” Opt. Express, Vol. 23, No. 10, pp. 13613-13618. (SCI, Optics, RF: 14/90=15.6%, IF:3.148)
34. Y. H. Cheng, C. W. Tsao, C. H. Chen and and W. J. Hsueh*, 2015, “Strong localization of photonics in symmetric Fibonacci superlattices,” J. Phys. D, Vol. 49, No. 295101, pp. 1-8. (SCI, Physics, Applied, RF: 31/145=21.4%, IF:2.772)
35. C. H. Chang, C. H. Chen, C. W. Tsao, and W. J. Hsueh*, 2015, “Superradiant modes in resonant quasi-periodic double-period quantum wells,” Opt. Express, Vol. 23, No. 9, pp. 11946-11951. (SCI, Optics, RF: 14/90=15.6%, IF:3.148)
36. R. Z. Qiu , C. H. Chang, Y. H. Cheng and W. J. Hsueh*, 2015, “Localized persistent spin currents in defect-free quasiperiodic rings with Aharonov-Casher effect,” Phys. Lett. A Vol. 379, pp. 1283-1287. (SCI, Physics, multidisciplinary, RF: 26/79=32.9%, IF:1.677)
37. C. H. Chang, Y. H. Cheng, and W. J. Hsueh*, 2014 “Twin extra high photoluminescence in resonant double-period quantum wells,” Opt. Lett., Vol. 39, No. 23, pp. 6581-6584. (SCI, Optics, RF: 11/87=12.6%, IF:3.292)
38. C. H. Chang, C. W. Tsao, and W. J. Hsueh*, 2014 “Superradiant modes in Fibonacci quantum wells under resonant non-Bragg conditions,” New J. Phys., Vol. 16, No. 113069. (SCI, Physics, multidisciplinary, RF: 10/78=12.8%, IF:3.558 )
39. C. W. Tsao, Y. H. Cheng, and W. J. Hsueh*, 2014, “Localized modes in one-dimensional symmetric Thue-Morse quasicrystals,” Opt. Express, Vol. 22, No. 20, pp. 24378-24383. (SCI, Optics, RF: 10/87=11.5%, IF:3.488)
40. R. Z. Qiu, C. H. Chen, C. W. Tsao, and W. J. Hsueh*, 2014 “High-Q filters with complete transports using quasiperiodic rings with spin-orbit interaction,” AIP Adv. Vol. 4, No. 9, pp. 097102. (SCI, Physics, Applied, RF:76/144=52.8%, IF: 1.524)
41. Y. H. Cheng, C. H. Chang, C. H. Chen, and W. J. Hsueh*, 2014 “Bragg-like interference in one-dimensional double-period quasicrystals,” Phys. Rev. A, Vol. 90, No. 023830. (SCI, Optics, RF:16/87=18.4%, IF: 2.808 )
42. C. H. Chen, R. Z. Qiu, C. H. Chang, and W. J. Hsueh*, 2014 “Strongly localized modes in one-dimensional defect-free magnonic quasicrystals,” AIP Adv. Vol. 4, No. 8, pp. 087102. (SCI, Physics, Applied, RF:76/144=52.8%, IF: 1.524)
43. R. Z. Qiu and W. J. Hsueh*, 2014, “Giant persistent currents in quasiperiodic mesoscopic rings,” Phys. Lett. A Vol. 378, pp. 851-855. (SCI, Physics, multidisciplinary, RF:26/78=33.3%, IF:1.683)
44. C. H. Chen and W. J. Hsueh*, 2014, “Enhancement of tunnel magnetoresistance in magnetic tunnel junction by a superlattice barrier,” Appl. Phys. Lett., Vol. 104, pp. 042405. (SCI, Physics, Applied, RF: 21/144=14.6%, IF:3.302)
45. W. J. Hsueh*, C. H. Chang, and C. T. Lin, 2014, “Exciton photoluminescence in resonant quasiperiodic Thue-Morse quantum wells,” Opt. Lett., Vol. 39, No. 3, pp. 489-492. (SCI, Optics, RF: 11/87=12.6%, IF:3.292)
46. C. M. Chang, M. H. Shiao, D. Chiang, S. W. Huang, C. T. Yang, C. T. Cheng, and W. J. Hsueh*, 2014, “The effects of ICP-RIE etching powers on the etching rate and surface roughness of the sapphire substrate,” J. Nanosci. Nanotechnol., Vol. 14 No. 10, pp. 8074-8078. (SCI, Materials science, multidisciplinary, RF: 134/260=51.5%, IF:1.556)
47. C. W. Tsao, W. J. Hsueh*, C. H. Chang, and Y. H. Cheng, 2013, “Quasi-Bragg conditions in Thue-Morse dielectric multilayers,” Opt. Lett., Vol. 38, No. 22, pp. 4562-4565. (SCI, Optics, RF: 10/83=12.0%, IF:3.179)
48. C. M. Chang, D. Chiang, M. H. Shiao, C. T. Yang, M. J. Huang, C. T. Cheng, and W. J. Hsueh*, 2013, “Dual layer photoresist complimentary lithography applied on sapphire substrate for producing submicron patterns,” Microsystem Technologies, Vol. 19 No. 11, pp1745-1751. (SCI, Engineering, electrical & electronic, RF:151/248=60.9%, IF:0.952)
49. W. J. Hsueh*, C. H. Chen and R. Z. Qiu, 2013, “Perfect transmission of spin waves in a one-dimensional magnonic quasicrystal,” Phys. Lett. A Vol. 377, pp. 1378-1385. (SCI, Physics, multidisciplinary, RF: 28/78=35.9%, IF:1.626)
50. Y. H. Cheng and W. J. Hsueh*, 2013, “High-Q filters with complete transmission by quasiperiodic dielectric multilayers,” Opt. Lett., Vol. 38, No. 18, pp. 3631-3634. (SCI, Optics, RF: 10/83=12.0%, IF:3.179)
51. D. Chiang*, C. M. Chang, S. W. Chen, C. T. Yang, and W. J. Hsueh, 2013, “Physical properties of an oxide photoresist film for submicron pattern lithography,” Thin Solid Films, Vol. 542, pp409-414. (SCI, Materials science, Coatings and films, RF:6/18=33.3%, IF:1.867)
52. W. J. Hsueh*, R. Z. Qiu and C. H. Chen, 2013, “Resonant transport and giant persistent currents in double-asymmetric rings”, Eur. Phys. J. B Vol. 86, pp. 27. (SCI, Physics, condensed matter, RF: 42/67=62.7%, IF:1.463)
53. C. H. Chang, C. H. Chen, and W. J. Hsueh*, 2013, “Strong photoluminescence emission from resonant Fibonacci quantum wells,” Opt. Express, Vol. 21, No. 12, pp. 14656-14661. (SCI, Optics, RF: 6/83=7.2%, IF:3.525)
54. C. M. Chang, M. H. Shiao, D. Chiang, C. T. Yang, M. J. Huang, W. J. Hsueh*, 2013, “Submicron-size patterning on the sapphire substrate prepared by nanosphere lithography and nanoimprint lithography techniques,” Met. Mater. Int., Vol. 19 No. 4, pp. 869-874. (SCI, Metallurgy, Metallurgical Engineering, RF:20/75=26.7%, IF:1.223)
55. W. J. Hsueh*, C. H. Chang, Y. H. Cheng, and S. J. Wun, 2012, “Effective Bragg conditions in a one-dimensional quasicrystal,” Opt. Express, Vol. 20, No. 24, pp. 26618-26623. (SCI, Optics, RF: 5/80=6.3%, IF:3.546)
56. M. H. Shiao, C. M. Chang, S. W. Huang, C. T. Lee, T. C. Wu, W. J. Hsueh, K. J. Ma, D. Chiang, 2012, “The sub-micron hole array in sapphire produced by inductively-coupled plasma reactive ion etching,” J. Nanosci. Nanotechnol., Vol. 12 No. 2, pp1641-1644. (SCI, Materials science, multidisciplinary, RF: 133/241=55.2%, IF:1.149)
57. W. J. Hsueh* and S. J. Wun, 2011, “Simple expressions for the maximum omnidirectional bandgap of bilayer photonic crystals,” Opt. Lett., Vol. 36, No. 9, pp. 1581-1583. (SCI, Optics, RF: 7/79=8.9%, IF:3.399)
58. W. J. Hsueh*, S. J. Wun, Z. J. Lin and Y. H. Cheng, 2011, “Features of the perfect transmission in Thue-Morse dielectric multilayers,” J. Opt. Soc. Am. B Vol. 28, No. 11, pp. 2584-2591. (SCI, Optics, RF: 18/79=22.8%, IF: 2.185)
59. W. J. Hsueh*, S. J. Wun, and C. W. Tsao, 2011, “Branching features of photonic bandgaps in Fibonacci dielectric heterostructures,” Opt. Commun. Vol. 284, No. 7, pp. 1880-1886. (SCI, Optics, RF:37/79=46.8%, IF:1.486)
60. W. J. Hsueh*, R. Z. Qiu and C. W. Wu, 2010, “Fractal property of band branching in Fibonacci mesoscopic rings,” J. Phys. Soc. Jpn. Vol. 79, No. 6, pp. 064704. (SCI, Physics, multidisciplinary, RF: 15/80=18.8%, IF: 2.905)
61. W. J. Hsueh*, C. H. Chen and C. H. Chang, 2010, “Bound states in the continuum in quasiperiodic systems,” Phys. Lett. A. Vol. 374, pp. 4804-4807. (SCI, Physics, multidisciplinary, RF:22/80=27.5%, IF:1.963)
62. W. J. Hsueh*, S. J. Wun and T. H. Yu, 2010, “Characterization of omnidirectional band gaps in multiple frequency ranges of one-dimensional photonic crystals,” J. Opt. Soc. Am. B Vol. 27, No. 5, pp. 1092-1098. (SCI, Optics, RF: 16/78=20.5%, IF: 2.097)
63. W. J. Hsueh*, C. H. Chen, and J. A. Lai, 2010, “Splitting rules of electronic miniband in Fibonacci superlattices: a gap map approach”, Eur. Phys. J. B Vol. 73, pp. 503-508. (SCI, Physics, condensed matter, RF: 29/68=42.6%, IF:1.575 )