2. COMSATS Institute Of Information &
Technology, Wah Cantt

3. CONTENTS:
INTRO.
QUANTUM
QUANTUM
INFLUENCE CONFINE-
DOTS
MENT
IMPORTANCE
COMSATS Institute Of Information &
Technology, Wah Cantt

4. INTRODUCTION:
“The early semiconductor work of Bell Labs in 1947 led to a
whole revolution in electronics”
One of the researchers expressed his thoughts as :
“When we discovered quantum confinement in
nano-crystals in the early 80’s, we knew this would be an
exciting area of scientific exploration and discovery”
DR. ALEXANDER EFROS
COMSATS Institute Of Information &
Technology, Wah Cantt

5. QUANTUM DOTS:
 A quantum dot is part of matter that confines in all three spactial
dimensions.
Materials like that have electronic properties intermediate between those
of bulk semiconductors and those of discrete molecules.
Exhibits energy band gap that determines required wave length of
radiation absorption and emission spectra.
Requisite absorption and resultant emission wave length depend on dot
size. COMSATS Institute Of Information &
Technology, Wah Cantt

6. QUANTUM CONFINEMENT:
 When the exciton is confined by the dimensions of the crystal to a space
that is smaller than the Bohr exciton radius, the wave function of the
electron is collapsed or limitized.
A quantum dot is a portion of matter comprises of Excitons.
The energy band gap increases with the decrease in size of quantum dot.
COMSATS Institute Of Information &
Technology, Wah Cantt

7. INFLUENCE:
A Next Step To Future Light Emitting Quantum Dots Silicon Wafers
Light Emitting Quantum Dot Solution Digital Televisions
COMSATS Institute Of Information &
Technology, Wah Cantt

8. CATAGORIES:
The nano tech. is further classified to distinguish its applications.
 Luminescent inorganic nano-crystals (Q-dots).
Now a days the most synthesised nano tech. examples are
CdTe Hydrophilic CdSe/ZnS Hydrophobicc ZnO:Mg
COMSATS Institute Of Information &
Technology, Wah Cantt

9. APPLICATIONS:
organic light emitting diodes (OLEDs) Ultra Coherence Tomography(UCT’s)
Quantum dots can be engineered to fluorescenceInformation & wave length’s based on physical
COMSATS Institute Of in different
Technology, Wah Cantt
dimensions

10. REVOLUTION IN MEDICAL SCIENCE
The use of quantum dots for biological imaging provides researchers and clinicians new and
versatile approaches to a range of biomedical challenges.
APPLICATIONS IN MEDICAL SCIENCE:
Drug delivery.
In vivo whole animal and clinical imaging (angiography).
Tissue mapping.
Environment and bio-defence.
Tracking cell migration (e.g., stem cells) .
COMSATS Institute Of Information &
Technology, Wah Cantt

11. COLORIFIC PROPERTIES AND OLED’S
The height and energy difference between energy levels increases as the size of QD’s
decreases.
SMALLER DOT = HIGHER ENERGY = SMALLER WAVE LENGTH
The three basic colors are combined to
form white light.
Since the QD’s are so small they can
be inserted in to anything to have
different color’s without changing their
characteristic properties.
COMSATS Institute Of Information &
Technology, Wah Cantt

12. ‘What I hear, I forget;
what I see, I remember;
what I do, I understand.’
Let’s do it together. We’ve heard what we have to do.
We’ve seen what we need to do.
Now is the time to do it, and, together, we can do it.”
COMSATS Institute Of Information &
Technology, Wah Cantt

13. QUERIES ARE SURELY GONNA BE
ENTERTINED
WILLINGLY
COMSATS Institute Of Information &
Technology, Wah Cantt