Magnetoresistance - Fodder for Micro Hard Drives
Kirt's Cogitations™ #139

RF Cafe University "Factoids," "Kirt's Cogitations," and "Tech Topics Smorgasbord" are all manifestations of my ranting on various subjects relevant (usually) to the overall RF Cafe theme. All may be accessed on these pages:

1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37

< Previous Next >

Magnetoresistance - Fodder for Micro Hard Drives

Researchers at SUNY, Buffalo, NY, have revealed the potential of an effect known as "ballistic magnetoresistance," whereby applying atomic-dimension "nanocontacts" to magnetic media resulted in a 3,000% change in magnetoresistance at low switching fields of a few hundred oersted. This has the potential to increase hard drive storage densities from GBits/in² to TBits/in². Interior magnetic-domain walls measure about 1 nm vs. 100 to 200 nm for a normal conductor. Electrons forced through such a small conduit literally do not have space to bounce around inside the conductor and producing heat. With a nanocontact's 1 nm wide domain walls, electrons stream through, creating a draft-like effect that prompted the label "ballistic." Look for thumbnail-size hard drives in about a decade.

Maury Microwave / Noisecom UFX 7000B Noise Generator - RF Cafe Website

RF Cafe began life in 1996 as "RF Tools" in an AOL screen name web space totaling 2 MB. Its primary purpose was to provide me with ready access to commonly needed formulas and reference material while performing my work as an RF system and circuit design engineer. The World Wide Web (Internet) was largely an unknown entity at the time and bandwidth was a scarce commodity. Dial-up modems blazed along at 14.4 kbps while tying up your telephone line, and a lady's voice announced "You've Got Mail" when a new message arrived...