JPS5952490A - Magnetic bubble memory element - Google Patents

Abstract

PURPOSE:To increase the detecting signal, by using at least one stage of pattern just before a detector larger than other patterns among plural stage of patterns formed in the progressing direction of bubbles in a bubble expander. CONSTITUTION:As one bit 9 just before a bubble detector 5, a pattern 10 having the shape of modified double chevron patterns and a large pitch is used in comparison with other patterns having a simple chevron pattern of the said bubble expander 6. That is, when the bubble detector uses a magneto-resistance effect, the phenomenon effected with the surrounding magnetic field is used positively and one several bits of the expander just before the detector are optimized to the detector and the detection signal of bubbles is increased in comparison with a conventional system. Since the state of bubbles just before the detector passes through the expander, the bubble is expanded fully and not effected largely with the pattern of several bits just before the detector. Thus, the detection signal is increased without blocking the expansion of the bubble.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a magnetic bubble memory element used as a storage device in an electronic computing device or a terminal thereof.

(2) Background of the technology Generally, magnetic thin films have an easy axis of magnetization of magnetic domains in the in-plane direction, but some materials, such as single crystals such as orthoferrite and magnetic garnet, have an easy axis of magnetization only in the C-axis direction. It has anisotropy. When a bias magnetic field of appropriate strength perpendicular to a single crystal thin film of such a material is applied, small cylindrical magnetic domains (called pulp) are formed perpendicular to the film surface.

This bubble can be moved by appropriately changing the external magnetic field. In the magnetic bubble memory, a large number of thin film fine turns made of permalloy are formed on the single-crystal M film to serve as a puzzle propagation path. 0"
It is used as memory in correspondence with

(3) Prior Art and Problems Conventionally, regarding the detection of magnetic bubbles in such a magnetic bubble memory, a bubble stretcher 1 and a detector 2 are provided as shown in FIG. The transmitted bubble 4 is greatly expanded by an expander 1 and then transferred to a detector 2. Therefore, the decompressor 1 is designed to repeatedly arrange the same pattern in several stages over several to several tens of bits in the transfer direction. The pattern of several bits of the expander immediately before the detector affects the magnetic field distribution near the detector, and is involved in the detection signal and its efficiency. However, conventional extenders are designed with emphasis on extending the bubble, and studies have been conducted to suppress the influence of the magnetic field on the detector, and the effect has not been actively utilized. There wasn't.

(4) Purpose of the Invention In view of the above conventional problems, the present invention provides a magnetic bubble memory that actively changes the magnetic field distribution near the detector 111 and destroys the bubble expander that increases the bubble detection signal. The purpose is to provide an element.

(5) Structure and object of the invention According to the present invention, a magnetic bubble generator, a bubble propagation path, a bubble stretcher, and a bubble stretched by the bubble stretcher are detected on a crystal film for magnetic bubbles. In a magnetic bubble memory device equipped with a bubble detector or the like, the bubble expander is arranged such that at least one stage immediately before the detector has a shape that is smaller than that of the other patterns among the patterns repeatedly formed in multiple stages in the bubble traveling direction. This is achieved by providing a magnetic bubble memory element characterized by the use of a unique pattern.

(6) Examples of the invention Embodiments of the present invention will be described below with reference to the drawings.

FIG. 2 is a diagram showing the expander and detector portions of the magnetic bubble memory device according to the present invention. In the figure, 5 is a bubble detector, 6 is a bubble expander, 7 is a bubble propagation path, and 8 is a bubble detector.
Each ill bubble is shown.

The bubble expander in this embodiment is a bubble detector 5 as shown in the figure. The previous 1-bit 9 uses a pattern 10 in which two modified chevron patterns are overlapped and the pitch is large, whereas the pattern in other parts of the bubble expander is a simple chevron pattern.

This embodiment formed in this way actively utilizes the phenomenon that is influenced by the surrounding magnetic field when the bubble detector uses the magnetoresistive effect. By optimizing several bits for the detector, the bubble detection signal is increased compared to the conventional method. Note that the state of the bubble just before entering the detector has been sufficiently expanded since it has passed through the decompressor, and is not affected too much by the pattern of several bits just before the detector.

Therefore, in this embodiment, the detection signal can be increased without inhibiting bubble expansion.

FIG. 3 is a characteristic diagram showing the bubble detection characteristics of the magnetic bubble memory element according to the present invention in comparison with a conventional example.

In the figure, the horizontal axis represents the driving magnetic field HD, and the vertical axis represents the detection efficiency (V Vo)/Vo (however, V.d, the output glaze and pressure when there is no baffle, and ■ the output box 5 when there is a bubble). 9. Curve A shows the case of the present invention in which the pattern 11 of 15 μm shown in the figure is used as the pattern immediately before the detector.
Curve B shows the case of the conventional example using the 10.5 μm pattern J2 shown in the figure. In this case, the extender pattern and the detector other than the pattern immediately before the detector are A.
, B use the same one.

It can be seen from the figure that the present invention is superior to the conventional example.

(7) Effects of the Invention As explained in detail above, the magnetic bubble memory device according to the present invention has the effect that the bubble detection signal can be increased compared to the conventional one by improving the bubble expander. It is a big thing.

[Brief explanation of the drawing]

FIG. 1 is a diagram showing a conventional bubble detector and expander for a magnetic bubble memory device, FIG. 2 is a diagram for explaining a bubble expander for a magnetic bubble memory device according to the present invention, and FIG. 3 is a diagram for explaining the bubble expander for a magnetic bubble memory device according to the present invention. FIG. 3 is a characteristic diagram showing the unexpected bubble detection efficiency of the magnetic bubble memory according to the present invention in comparison with a conventional one. In the drawings, 5 is a bubble detector, 61-J is a bubble expander, 7 is a bubble propagation path, and 8 is a bubble.

Claims (1)

[Claims] 1. A magnetic bubble memory element equipped with a magnetic bubble generator, a bubble propagation path, a bubble expander, a bubble detector for detecting bubbles expanded by the bubble expander, etc. on a magnetic bubble crystal film, The bubble expander is a magnetic bubble memory characterized in that among patterns repeatedly formed in a plurality of stages in the bubble traveling direction, at least one stage immediately before the detector uses a pattern having a larger shape than the other patterns. element.