How to stop the animation at a particular point?

Question

I have created this animation for displaying a profile and I want to stop the animation when the profile picture animation is completed and before the opacity of the text below starts to change. Now, I know that the profile picture animation changes from 0.3 to 0.6 and so I want to stop the animation at 0.6. Here is the code.

import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:google_fonts/google_fonts.dart';

class profile extends StatefulWidget {
@override
_profileState createState() => _profileState();
}

class _profileState extends State<profile> with SingleTickerProviderStateMixin{

AnimationController _animationController;

Animation<double> barHeight;
Animation<double> avatarSize;
Animation<double> textOpacity;


@override
void initState() {
// TODO: implement initState
super.initState();
_animationController = AnimationController(vsync: this,duration: Duration(seconds: 5));
_animationController.forward();

barHeight = Tween(begin: 0.0,end: 250.0).animate(CurvedAnimation(parent:_animationController,curve: 
Interval(0.1,0.3,curve:Curves.easeInOutQuint)));
avatarSize = Tween(begin: 0.0,end: 1.0).animate(CurvedAnimation(parent:_animationController,curve: 
Interval(0.3,0.6,curve:Curves.easeInOutCirc)));
textOpacity = Tween(begin: 0.0,end: 1.0).animate(CurvedAnimation(parent:_animationController,curve: 
Interval(0.6,1,curve:Curves.easeInOutCirc)));



}


Widget _buildanimation(BuildContext context,Widget child, Size size){
return Container(
  decoration: BoxDecoration(
    image: DecorationImage(
      image: AssetImage('assets/bgi1.png'),
      fit: BoxFit.fill
    )
  ),
  child: Column(
    children: <Widget>[
      SizedBox(height: 250,
        child: Stack(
          overflow: Overflow.visible,
          children: <Widget>[
            Opacity(
              opacity: 0.9,
              child: Container(
                height: barHeight.value,
                width: double.infinity,
                decoration: BoxDecoration(
                image: DecorationImage(
                  image: AssetImage('assets/books.jpg'),
                  fit: BoxFit.fitWidth
                )
                ),
              ),
            ),
            Positioned(
              top: 200,
              left: size.width/2-70,
              child: Transform(
                alignment: Alignment.center,
                transform: Matrix4.diagonal3Values(avatarSize.value, avatarSize.value, 1.0),
                child: Container(
                  width: 120,
                  height: 120,
                  decoration: BoxDecoration(
                      borderRadius: BorderRadius.circular(100),
                  ),
                  child: CircleAvatar(
                    backgroundImage: AssetImage('assets/profile.jpg'),
                  ),
                ),
              ),
            ),
          ],
        ),
      ),

          Padding(
            padding: const EdgeInsets.all(12),
            child: Column(
              children: <Widget>[
                SizedBox(height: 60,),
                Opacity(opacity:textOpacity.value,
                    child: Text(
                        "Gillian Flynn",
                      style: GoogleFonts.lobster(fontSize: 50,color: Colors.blue[900]),
                    )),
                SizedBox(height: 40,),
                Opacity(opacity:textOpacity.value,child: Padding(
                  padding: const EdgeInsets.all(10.0),
                  child: Text(
                      "Gillian Flynn was born in Kansas City, Missouri to two community-college 
professors—her mother taught reading; her father, film. Thus she spent an inordinate amount of her 
youth nosing through books and watching movies. She has happy memories of having A Wrinkle in Time 
pried from her hands at the dinner table, and also of seeing Alien, Psycho and Bonnie and Clyde at a 
questionable age (like, seven). It was a good childhood.",
                    style: GoogleFonts.kanit(fontSize: 15),

                  ),
                ))
              ],
            )
        ),
    ],
  ),
);
}

@override
void dispose() {
// TODO: implement dispose
super.dispose();
_animationController.dispose();
}



@override
Widget build(BuildContext context) {
final size = MediaQuery.of(context).size;
return Scaffold(
  body: AnimatedBuilder(
    animation: _animationController,
    builder: (context,child)=> _buildanimation(context,child,size),
  )
);
}
}

I am asking this because I want to know if I can perform specific intervals of animations alone using one animationcontroller itself.