It is estimated that at least ........ data are generated every day. • Brain’s memory capacity is in the terabytes range, as much as entire web. • The size of text collections in library of congress is approx ten terabytes. • A standard Optical disc can store around 360 terabytes of data with an estimate life span of up to 13.8 billion years even at temperatures of 190 degree Celsius. Introduction  It is estimated that at least ........ data are generated every day.  Brain’s memory capacity is in the terabytes range, as much as entire web.  The size of text collections in library of

1. Glass Computer Memory
By
Bubai Das
Department of Computer Science
West Bengal State University

2. Introduction
• It is estimated that at least ........ data are generated
every day.
• Brain’s memory capacity is in the terabytes range, as
much as entire web.
• The size of text collections in library of congress is
approx ten terabytes.
• A standard Optical disc can store around 360
terabytes of data with an estimate life span of up to
13.8 billion years even at temperatures of 190 degree
Celsius.
Introduction
 It is estimated that at least Million terabytes data are
generated every day.
 A standard Optical disc can store around 360
terabytes of data.
 Lifespan up to 13.8 billion.

3. What is Glass Memory Disk Technology
•A nanostructure glass for permanently recording 5-D
digital data.
•Using femtosecond laser
•This is first done in 2013
•It was created by a team of Scientists at the university
of Southampton in England.
•Data encoded in 5-Dimension.
What is Glass Memory Disk Technology
•A nanostructure glass for permanently recording
5-D digital data.
•Using femtosecond laser
•It was created by a team of Scientists at the
university of Southampton in England.

4. Femtosecond laser direct writing : The
principle
• Tight focusing of laser beam(e.g
lambda=800nm,del r =100fs)
• Into transparent material
• High intensity leading to multi photon absorption
• Structural changes in matter confined to focal
volume due to short pulse duration=3D
Dimensions of data storage and parameter used to identify
each bit of DATA :
• 3 spatial dimensions
• Colour
• Polarization
Concept of 5-D storage technology

5. Femtosecond laser direct writing : The
principle
• Tight focusing of laser beam(e.g
lambda=800nm,del r =100fs)
• Into transparent material
• High intensity leading to multi photon absorption
• Structural changes in matter confined to focal
volume due to short pulse duration=3D
4th and 5th dimensions: Retardance and
slow axis angle
Nanogratings produce birefringence characterize
by two parameters.
 (4thD) Retardance R
 (5thD)slow axis angle Θ

6. History of data storage
Punch Cards (80
Character)
Punched
Tape(1000
character)
Selection
Tubes(4096Bits)
Magnetic
Tape(5MB to
140MB)
Floppy
Disk(256kb)
Hard
Drive(80gb-1TB)
Compact
Disc(700mb)
DVD(4.7gb)
Femtosecond laser direct writing : The
principle
Tight focusing of laser beam(e.g lambda=800nm,del
r =100fs)
Into transparent material
High intensity leading to multi photon absorption
Structural changes in matter confined to focal volume
due to short pulse duration=3D
Femtosecond laser direct writing : The
principle
 Tight focusing of laser beam(E.g
λ =800nm,del r =100fs)
 Into transparent material
 High intensity leading to multi
photon absorption
 Structural changes in matter confined
to focal volume due to short pulse
duration.

7. Femtosecond laser direct writing : The
principle
• Tight focusing of laser beam(e.g
lambda=800nm,del r =100fs)
• Into transparent material
• High intensity leading to multi photon absorption
• Structural changes in matter confined to focal
volume due to short pulse duration=3D
3D optical storage by femtosecond laser
writing
Picoseconds (10*10-12) laser
induces voids with external
stress
Femtosecond (100*10-15)
laser induced small void in
quartz glass

8. Femtosecond laser direct writing : The
principle
• Tight focusing of laser beam(e.g
lambda=800nm,del r =100fs)
• Into transparent material
• High intensity leading to multi photon absorption
• Structural changes in matter confined to focal
volume due to short pulse duration=3D
Stability
Parameters CD DVD Blue-ray 5-D
Capacity 0.7 GB 4.7 GB 23.5 GB
360 Tb per
disk
Longevity 5 Years 7 Years 7 years 1020 years
Speed
1.2
Megabyte/s
10.5
Megabyte/s
36
Megabyte/s
20
Megabyte/s
Advantages of 5D in quartz glass: High capacity, Long life time
Magnetic tape
Optical disk
Flash
SSD
HDD M-DISK
Void-based
Fused silica disk
5D Optical
memory
years
1 10 100 1000 ........ ... 108 1010

9. Femtosecond laser direct writing : The
principle
• Tight focusing of laser beam(e.g
lambda=800nm,del r =100fs)
• Into transparent material
• High intensity leading to multi photon absorption
• Structural changes in matter confined to focal
volume due to short pulse duration=3D
Thermal stability
Using the Arrhenius law, The lifetime can be extrapolated To the room
T = 30° → 𝜏 = 300*1018 years

10. Femtosecond laser direct writing : The
principle
• Tight focusing of laser beam(e.g
lambda=800nm,del r =100fs)
• Into transparent material
• High intensity leading to multi photon absorption
• Structural changes in matter confined to focal
volume due to short pulse duration=3D
How Data Stores
Data in documents was recorded using ultra fast laser
producing very short and intense pulses of light the file
is written in three layers of nanostructure dots separated
by five micro meters.

11. Femtosecond laser direct writing : The
principle
• Tight focusing of laser beam(e.g
lambda=800nm,del r =100fs)
• Into transparent material
• High intensity leading to multi photon absorption
• Structural changes in matter confined to focal
volume due to short pulse duration=3D
Writing
 Tunable Laser is used: Titanium Femtosecond Laser.
 Light impinging with a certain colour and polarization will
only target a subpopulation of gold nanorods, leaving the
remaining rods for the next recording.
Retardance Slow axis angle
Data writing

12. Reading
• Reading performed by 2 Photon luminescence.
• Nanorods shine as they absorb light with the same
wavelength and polarization that changed their shape
during recording.
Reading
• Reading performed by 2 Photon luminescence.
• Nanorods shine as they absorb light with the same wavelength
and polarization that changed their shape during recording.
• Various quantities birefringence measurement system.
• It is characterized by universal liquid crystal analyzer

13. Data Printing On The Glass
5D optical data storage written in fused
quartz using a femtosecond laser three spatial
dimension and two optical ones are exploited

14. • “Optical” recording has been used for ever ,10,000
year in human data recording historyLongevity
• Since there is no contact with the medium surface
there is less probability of abrasion , scratch or other
medium wear.
Contactless
• Only data stored in optical disk survived hurricaneSurvivability
• Since BD can be read on general purpose ..... With
consumer devices .... Is .. Logs possibility that media
and data will be inaccessible due to absolute devices
Compatibility
• “Optical” recording has been used for ever,
10,000 year in human data recording historyLongevity
• Since there is no contact with the medium
surface there is less probability of abrasion ,
scratch or other medium wear.
Contactless
• Only data stored in optical disk survived
hurricaneSurvivability
Optical data storage benefits

15. Disadvantages
1. Slow writing speed.
2. Not easily re- writable.
3. Cost Concerns.

16. • Optical data storage with practically unlimited
lifetime in ultrafast laser nanostructure quartz glass is
demonstrated.
• For the first time , Storage technology might allow
human knowledge to outlive us.
• These is more useful for organisation, we can store
the data safely for billion years.
Conclusion

17. [1] Nanophotonics Down Under 2009 Devices and
Applications - www.swinburne.edu.au
[2] Nano-particle Based Multi-Dimensional Data Storage. By
Xiangping Li (Thesis) - www.tr.im/5DDVD
[3] Five dimensional optical recording - http://u.nu/5fxr
[4] Nanotech DVD - http://u.nu/7fxr
[5] Five dimensional optical recording (journal) -
http://u.nu/9fxr
[6] Five dimensional optical recording - Technology Review
(digital magazine) - (Published by MIT) - http://u.nu/3gxr
REFERENCES
References