Erasable conductive domain walls in insulating ferroelectric thin films can be used for non-destructive electrical read-out of the polarization states in ferroelectric memories. Still, the domain-wall currents extracted by these devices have not yet reached the intensity and stability required to drive read-out circuits operating at high speeds. This study demonstrated non-destructive read-out of digital data stored using specific domain-wall configurations in epitaxial BiFeO thin films formed in mesa-geometry structures. Partially switched domains, which enable the formation of conductive walls during the read operation, spontaneously retract when the read voltage is removed, reducing the accumulation of mobile defects at the domain walls and potentially improving the device stability. Three-terminal memory devices produced 14 nA read currents at an operating voltage of 5 V, and operated up to T = 85 °C. The gap length can also be smaller than the film thickness, allowing the realization of ferroelectric memories with device dimensions far below 100 nm.

Emerging for future spintronic/electronic applications, magnetic semiconductors have stimulated intense interest due to their promises for new functionalities and device concepts. So far, the so-called diluted magnetic semiconductors attract many attentions, yet it remains challenging to increase their Curie temperatures above room temperature, particularly those based on III–V semiconductors. In contrast to the concept of doping magnetic elements into conventional semiconductors to make diluted magnetic semiconductors, here we propose to oxidize originally ferromagnetic metals/alloys to form new species of magnetic semiconductors. We introduce oxygen into a ferromagnetic metallic glass to form a Co28.6Fe12.4Ta4.3B8.7O46 magnetic semiconductor with a Curie temperature above 600 K. The demonstration of p–n heterojunctions and electric field control of the room-temperature ferromagnetism in this material reflects its p-type semiconducting character, with a mobility of 0.1 cm2 V−1 s−1. Our findings may pave a new way to realize high Curie temperature magnetic semiconductors with unusual multifunctionalities.

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Jacaranda mimosifolia of 55-year-old in Sichuan Neijiang was selected as test material. Through the observation of its growth and development by 2011 and the analysis of temperature and relative humidity, this study discussed its basic law of growth and development and the relationship between temperature and RH factor. By analysis of variance, there was no significant difference in monthly average temperature and RH between 2011 and the climate in Neijiang, the temperature and RH of 2011 could reflect the situation of Neijiang regional climatic. The results showed that the average annual growth of J. mimosifolia new shoot was 32.4cm and the average thickness was 11.2mm, and appeared thrice sprouting and twice flowering phenomenon per year. Combined the characteristics of growth and development of J. mimosifolia, the length and thickness of spring shoot, summer shoot and autumn shoot were both extremely different (P<0.01), and two florescence appeared in Spring and Autumn when the temperature was not different significantly. Therefore, temperature played an apparently predominant role in its growth and development.