FRG: Study of Pi-Conjugated Organic Semiconductors with Tailored Spin-Orbit Coupling

FRG：利用定制自旋轨道耦合研究 Pi 共轭有机半导体

• 批准号: 0503172
• 负责人: Zeev Valy Vardeny
• 金额: $ 48万
• 依托单位: University of Utah
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2005
• 资助国家: 美国
• 起止时间: 2005-07-01 至 2008-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0503172&HistoricalAwards=false
• 关键词: FRG; Study; Pi; Conjugated; Organic

Technical. This focused research group project is a collaborative effort among researchers with expertise in Organic Materials Science and Chemistry, Optics, Optoelectronics, Magneto-transport and Theoretical Physics. Intellectual Merit: The goals of the research are the synthesis, study of electronic and spin phenomena, and optoelectronic/spintronics applications of novel p-conjugated semiconductor systems that include heavy atoms such as platinum in their backbone structure, in order to tailor the spin-orbit coupling of the p-electron excitations. The increased spin-orbit (SO) coupling would enhance the singlet to triplet intersystem crossing, leading to a large triplet yield. It would also result in a strong phosphorescence (PH) emission band that is red-shifted with respect to the usual photoluminescence (PL) band. The large, tailored triplet yield would enable the study of high-density triplets, including their collective spin coherence properties for possible quantum manipulation of spin-qubits. The approach includes: (i) synthesis of Pt- and Ir- containing p- conjugated systems including monomers, polymers and co-polymers using new synthesis techniques, with control over the number of the heavy atoms in the backbone structure. (ii) measurement of optical and spin properties of singlet and triplet excitons, including ps time resolved response, the nature of the PH and PL emission bands, spin randomization of charge polarons, and spin coherence phenomena of triplet excitons using zero-field optically detected magnetic resonance (ODMR). (iii) study of collective spin coherence properties of triplets at high density via the manifestation of collective Rabi oscillations in the PH-ODMR where triplets are locked together via their mutual superradiance interaction coupling when applying a strong, resonant microwave radiation, and also by analyzing the PH noise spectrum. (iv) fabrication of spin organic light emitting diodes (S-OLED) with ferromagnetic spin-injecting electrodes and heavy-atom polymers, for studying the interplay of electro-PL and electro-PH emissions upon application of an external magnetic field to spin aligned carrier injection and transport. The theory team will support the research activity by providing highly necessary feedback to the experimentalists; this includes understanding of collective Rabi oscillations at high triplet density, Rabi oscillations nutation, analysis of PH emission noise, and a magneto-phonon resonance within the triplet spin sublevels. Non-Technical. Broader Impact: Research outcomes may include novel optoelectronic applications such as S-OLED and spin qubits for quantum computers. In addition the integration of experimental and theoretical efforts, including polymer synthesis, cw and ultrafast optics, magneto-transport, theoretical physics methods, and device fabrication, processing and testing, is expected to provide broad educational opportunities for graduate and undergraduate students.

技术上的。这个重点研究小组项目是有机材料科学和化学、光学、光电子学、磁传输和理论物理方面的专业研究人员共同努力的结果。智力价值：这项研究的目标是合成、研究电子和自旋现象，以及新型p-共轭半导体系统的光电子/自旋电子学应用，这些系统的主干结构中包括铂等重原子，以便定制p-电子激发的自旋-轨道耦合。增强的自旋-轨道(SO)耦合将增强单态到三态的系间交叉，导致较大的三态产额。它还将导致相对于通常的光致发光(PL)带红移的强磷光(PH)发射带。大的、量身定做的三重态产额将使研究高密度三重态成为可能，包括它们的集体自旋相干性质，以可能对自旋量子比特进行量子操作。该方法包括：(I)利用新的合成技术，通过控制主链结构中重原子的数量，合成包括单体、聚合物和共聚物在内的含铂和含Ir的p-共轭体系。(Ii)利用零场光学探测磁共振(ODMR)测量单态和三态激子的光学和自旋性质，包括PS时间分辨响应、PH和PL发射带的性质、电荷极化子的自旋随机化和三态激子的自旋相干现象。(Iii)通过PH-ODMR中集体拉比振荡的表现，研究了高密度下三重态的集体自旋相干性，其中三重态在强共振微波辐射作用下通过相互超辐射相互作用耦合被锁定在一起，并通过分析PH噪声谱来研究。(4)制备具有铁磁性自旋注入电极和重原子聚合物的自旋有机电致发光二极管(S-OLED)，用于研究外加磁场对自旋定向载流子注入和输运时电致发光和电致发光的相互作用。理论团队将通过向实验者提供非常必要的反馈来支持研究活动；这包括了解高三重态密度下的集体拉比振荡、拉比振荡章动、PH发射噪声的分析以及三重态自旋子能级内的磁声子共振。非技术性。更广泛的影响：研究成果可能包括新颖的光电应用，如S有机发光二极管和量子计算机的自旋量子比特。此外，实验和理论努力的整合，包括聚合物合成、连续波和超快光学、磁传输、理论物理方法以及器件制造、加工和测试，预计将为研究生和本科生提供广泛的教育机会。